Display module and display system

ABSTRACT

Disclosed is a display module including a transparent display panel and a frame to fix a side of the transparent display panel, wherein the frame has a communication unit to receive data from the outside, a controller to process the received data and to output a drive command corresponding to the processed data and a display drive unit to drive the transparent display panel in response to the drive command from the controller. A display system includes a system body and a display module detachably mounted in the system body.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No.10-2011-0040408, filed on Apr. 28, 2011 in the Korean IntellectualProperty Office, and U.S. Patent Application No. 61/407,449, filed onOct. 28, 2010 in the U.S. Patent and Trademark Office these disclosureof which is incorporated herein by reference.

BACKGROUND

1. Field

Exemplary embodiments of the present invention relate to a displaymodule and a display system that maximize visual and spatial utilizationusing a transparent display panel.

2. Description of the Related Art

Display devices that provide information to human have been very rapidlydeveloped from an early cathode ray tube (CRT) type monochrome displaydevice, which has a large volume, to a recent thin film type large-areafull color display device.

Also, the display devices have been rapidly developed from a device thatdisplays only a simple message and image to a more sophisticated devicethat displays beauty.

The display devices have a clearly visible form. When the displaydevices are installed in houses or public places, therefore, the displaydevices occupy large spaces with the result that spatial utilization islow. Also, the display devices may function as visual obstacles with theresult that an aesthetically pleasing space is not provided and use ofthe display devices is limited.

SUMMARY

Exemplary embodiments of the present inventive concept may overcome theabove disadvantages and other disadvantages not described above. Also,the present inventive concept is not required to overcome thedisadvantages described above, and an exemplary embodiment of thepresent inventive concept may not overcome any of the problems describedabove.

An aspect of the present invention provides a display module which mayinclude: a transparent display panel; and a frame which fixes a side ofthe transparent display panel, wherein the frame has a communicationunit which may be operable to receive data, a controller which may beoperable to process the received data and to output a drive commandbased on the processed data and a display drive unit which may beoperable to drive the transparent display panel in response to the drivecommand from the controller.

The transparent display panel may have a greater surface area than theframe and a smaller thickness than the frame.

The transparent display panel may be partially fitted in the frame.

The display module may further include a storage unit provided in theframe to store at least one data, wherein the controller may be operableto control the data stored in the storage unit to be displayed.

The controller may include a first signal processing unit to process thedata received by the communication unit and a second signal processingunit to process the data stored in the storage unit.

The display module may further include an input unit provided in theframe to allow the data received by the communication unit or the datastored in the storage unit to be selected, wherein the controllercontrols the selected data to be displayed.

If a plurality of data is stored in the storage unit, the input unit mayallow one of the data stored in the storage unit to be selected.

The input unit may allow one of modes to be selected and the controllercontrols an image corresponding to the selected mode to be displayed.

The storage unit may store data for each time and the controller mayconfirm a current time, determine whether data corresponding to theconfirmed time are present and control retrieved data to be displayedwhen the retrieved data are present.

The communication unit may be operable to perform wireless communicationand the controller and to process data received through the wirelesscommunication.

The frame may have a hole and a power supply unit connected to anexternal power source through the hole to receive power and to convertthe received power into drive power to drive the display module.

The power supply unit may include ea rechargeable power supply unit.

The display module may further include a blocking member operable toblock light, wherein the blocking member may be provided at an edge ofthe transparent display panel.

The display module may further include an anti-reflective coating filmoperable to prevent light from being reflected by the transparentdisplay panel, wherein the reflective coating film may be providedadjacent to the transparent display panel.

The display module may further include a heat insulation sheet operableto block heat generated from transparent display panel from beingdischarged, wherein the heat insulation sheet may be adjacent to thetransparent display panel.

The communication unit may receive a broadcast signal.

The transparent display panel may be operable to display images togetherwith another transparent display panel in a multi display performancemode in response to a command from a server.

The frame may have a recognition unit operable to recognize a tag andthe controller may be further operable to read the recognized tag andcontrol an image corresponding to the read data to be displayed on thetransparent display panel.

Another aspect of the present invention provides a display system whichmay include: a system body having a first power supply unit; and adisplay module detachably mounted in the system body, wherein thedisplay module may include a transparent display panel, a frame whichfixes the transparent display panel, and a drive module provided in theframe operable to convert power from the first power supply unit intodrive power and operable to control driving of the transparent displaypanel.

The drive module may include at least one printed circuit board.

The drive module may include a communication unit to receive datatransmitted from a server, a controller to process the received data andto output a drive command corresponding to the processed data, a displaydrive unit to drive the transparent display panel in response to acommand from the controller so that the data are displayed on thetransparent display panel and a second power supply unit to convertpower from the first power supply unit into drive power of thecommunication unit, drive power of the controller and drive power of thedisplay drive unit.

At least two selected from a group including the communication unit, thecontroller, the display drive unit and the second power supply unit maybe provided in the at least one printed circuit board.

The first power supply unit may be connected to a commercial powersource and the second power supply unit may be connected to the firstpower supply unit via a cable to receive power.

The display system according to claim 23, further comprising a firsthole provided at the system body and a second hole provided at the frameof the display module, wherein the cable extends from the system body tothe frame through the first hole and the second hole.

The display system may further include: a storage unit provided in thedrive module to store at least one data; and an input unit provided inthe frame and electrically connected to the controller to allow the datareceived by the communication unit or the data stored in the storageunit to be selected, wherein the controller may confirm the dataselected through the input unit and control the confirmed data to bedisplayed.

If a plurality of data is stored in the storage unit, the input unit mayallow one of the data stored in the storage unit to be selected.

The input unit may allow one of modes to be selected and the controllercontrols an image corresponding to the selected mode to be displayed.

The display system may further include a blocking member operable toblock light, wherein the blocking member is provided at the remainder ofthe transparent display panel wherein the blocking member may bedisposed at an edge of the transparent display panel.

The system body comprises a showcase including a main body, an openingat one side of the main body and a storage chamber in the main body,wherein the display module may be mounted in the opening of theshowcase.

The display system may further include an anti-reflective coating filmoperable to reduce external light reflected by the transparent displaypanel, wherein the anti-reflective coating film may be adjacent to thetransparent display panel.

The display system may further include a heat insulation sheet operableto reduce heat discharged from transparent display panel to the storagechamber, wherein the heat insulation sheet may be at a side of thetransparent display panel facing the storage chamber.

The showcase may further include a door mounted at the opening and thedisplay module may be mounted at the door of the showcase.

The display system may further include a detection unit, which may beprovided in the frame and electrically connected to the controller, andwhich may be operable to detect at least one of opening and closing ofthe door of the showcase and to output a door signal, wherein thecontroller may be further operable to determine whether the door is openbased on a door signal and to control an image displayed on thetransparent display panel to be reversed upon determining that the dooris open.

The controller may count door open time upon determining that the dooris open and may control the door to be closed if the counted timeexceeds reference time.

The controller may confirm an opening angle of the door based on thedoor opening and closing signal, compare the opening angle of the doorwith a reference angle and control an image displayed on the transparentdisplay panel to be reversed upon determining that the opening angle ofthe door exceeds the reference angle.

The display system may further include a detection unit, which may beprovided in the main body, and which may be operable to detect atemperature of the storage chamber, wherein the controller may beoperable to determine whether the door is open based on a change in thetemperature of the storage chamber and may be operable to control animage displayed on the transparent display panel to be reversed upondetermining that the door is open.

The display system may further include a detection unit, which may beprovided in the frame and electrically connected to the controller, andwhich may be operable to detect a human body and to output a human bodydetection signal, wherein the controller may be further operable toadjust a transparency of the transparent display panel based upon thehuman body detection signal.

The display system may further include a recognition unit, which may beprovided in the frame and electrically connected to the controller, andwhich may be to recognize a tag, wherein the controller may controltailored information of a customer possessing the tag to be displayedbased upon data of the recognized tag.

The communication unit may communicate with a customer terminal and thecontroller may confirm information regarding a customer and controls theconfirmed tailored information of the customer to be displayed.

The controller may request the tailored information of the customer froma server and may receive the tailored information of the customer fromthe server.

The display system may further include a recognition unit to recognize acode printed on an article to be stored in the storage chamber of theshow case, wherein the controller may read the recognized code andstores the read data.

Another aspect of the present invention provides a display system whichmay include: a system body having a first power supply unit; and aplurality of display modules detachably mounted in the system body,wherein each of the display modules may include a transparent displaypanel, a frame which fixes the transparent display panel and a drivemodule in the frame operable to convert power from the first powersupply unit into drive power and operable to control driving of thetransparent display panel.

The display system may further include a server to communicate with thedisplay modules and to control driving of the display modules, whereinthe server may process data input by a user or data received from anoutside and may distribute and transmit the processed data to thedisplay modules.

The server may transmit the same data so that the same image isdisplayed on the display modules.

The server may control different images to be displayed on the displaymodules.

The server may transmit the same data to some of the display modules anddifferent data to the remainder of the display modules.

The display modules may be slidably mounted in the system body.

Each of the display modules may have a second power supply unit toconvert power from the first power supply unit to drive power.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects of the invention will become apparent andmore readily appreciated from the following description of the exemplaryembodiments, taken in conjunction with the accompanying drawings ofwhich:

FIG. 1 is a perspective view of a display system according to anexemplary embodiment of the present invention;

FIG. 2 is a view illustrating the interior of the display systemaccording to the exemplary embodiment of the present invention;

FIG. 3 is a view illustrating the interior of a display module providedin the display system according to the exemplary embodiment of thepresent invention;

FIGS. 4A to 4D are views illustrating the structure of a transparentdisplay panel provided in the display system according to the exemplaryembodiment of the present invention;

FIGS. 5 and 6 are views illustrating extension of a cable between a mainbody of the display system according to the exemplary embodiment of thepresent invention and the display module;

FIG. 7 is a control block diagram of the display system according to theexemplary embodiment of the present invention;

FIG. 8 is a control block diagram of a display system according toanother exemplary embodiment of the present invention;

FIG. 9 is a detailed control block diagram of the display systemaccording to the exemplary embodiment of the present invention;

FIG. 10 is a view illustrating a reversed state of a display moduleprovided in the display system according to the exemplary embodiment ofthe present invention;

FIGS. 11( a) to 11(c) are views illustrating prediction of door openingangles of a showcase according to another exemplary embodiment of thepresent invention;

FIG. 12 is a view illustrating the structure of a touch display panelprovided in a display system according to another exemplary embodimentof the present invention;

FIG. 13 is a control block diagram of a display system according toanother exemplary embodiment of the present invention;

FIG. 14 is a view illustrating multi display performance of a displaysystem according to another exemplary embodiment of the presentinvention;

FIG. 15 is a view illustrating multi display performance of a displaysystem according to another exemplary embodiment of the presentinvention;

FIG. 16 is a perspective view of a display system according to anotherexemplary embodiment of the present invention;

FIG. 17 is a view illustrating installation of a display module of thedisplay system according to the exemplary embodiment of the presentinvention;

FIGS. 18 and 19 are perspective views of a display system according toanother exemplary embodiment of the present invention;

FIG. 20 is a front perspective view of a television, as a displaymodule, according to another exemplary embodiment of the presentinvention;

FIG. 21 is a rear perspective view of the television according to theexemplary embodiment of the present invention;

FIG. 22 is a control block diagram of the television according to theexemplary embodiment of the present invention;

FIG. 23 is a detailed control block diagram of the television accordingto the exemplary embodiment of the present invention;

FIG. 24 is a view illustrating a bus shelter, as a display module,according to another exemplary embodiment of the present invention;

FIG. 25 is a control block diagram of the bus shelter according to theexemplary embodiment of the present invention;

FIG. 26 is a view illustrating application of the bus shelter accordingto the exemplary embodiment of the present invention;

FIG. 27 is a view illustrating the bus shelter according to theexemplary embodiment of the present invention;

FIGS. 28A and 28B are perspective views of a information board, as adisplay module, according to another exemplary embodiment of the presentinvention;

FIG. 29 is a view illustrating application of the information boardaccording to the exemplary embodiment of the present invention;

FIG. 30 is a control block diagram of the information board according tothe exemplary embodiment of the present invention;

FIG. 31 is a view illustrating a show window, as a display module,according to another exemplary embodiment of the present invention;

FIG. 32 is a view illustrating a window, as a display module, accordingto another exemplary embodiment of the present invention;

FIG. 33 is a view illustrating a floor mat, as a display module,according to yet another exemplary embodiment of the present invention;and

FIG. 34 is a view illustrating the structure of the floor mat accordingto the exemplary embodiment of the present invention.

DETAILED DESCRIPTION

Reference will now be made in detail to the exemplary embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to like elementsthroughout.

A display system includes a main body and a display module detachablymounted in the main body.

The display module includes a transparent display panel, a frame to fixthe transparent display panel and a drive module mounted in the frame tocontrol driving of the transparent display panel.

The main body may be a cooking device, such as a showcase, arefrigerator, a Kimchi refrigerator, a microwave oven or a gas oven. Thedisplay module may be fixed to an opening of the showcase, therefrigerator or the Kimchi refrigerator. Also, the display module may beused as a door.

The showcase stores and displays articles, such as ornaments, food,flowers, drugs, clothes, bowls, books or works of art. The showcaseincludes a display module provided at an opening of the main body todisplay an image.

Therefore, people may view the image to recognize articles in theshowcase. The display module may be formed partially or wholly at theopening.

Hereinafter, the display system will be described in detail withreference to the drawings.

FIG. 1 is a perspective view of a display system according to anexemplary embodiment of the present invention, FIG. 2 is a viewillustrating the interior of the display system according to theexemplary embodiment of the present invention, FIG. 3 is a viewillustrating the interior of a display module provided in the displaysystem according to the exemplary embodiment of the present invention,FIGS. 4A to 4D are views illustrating the structure of a transparentdisplay panel provided in the display system according to the exemplaryembodiment of the present invention, FIGS. 5 and 6 are viewsillustrating extension of a cable between a main body of the displaysystem according to the exemplary embodiment of the present inventionand the display module, and FIG. 7 is a control block diagram of thedisplay system according to the exemplary embodiment of the presentinvention.

In this exemplary embodiment, the display system includes arefrigerating showcase, as a system body 100, to keep food fresh and adoor, as a display module 200, mounted at an opening of the main body ofthe showcase.

As shown in FIGS. 1 and 2, the refrigerating showcase, as the systembody 100, includes a main body 110, a storage chamber 120, shelves 130,a machine compartment 140, and a cool air generating compartment 150.

The main body 110 forms the external appearance of the showcase.

The storage chamber 120 to store food is defined in the main body 110.The main body 110 is provided at the front thereof with a mountingmember 111 and a protective member 112. Also, an opening 113 is formedat the front of the main body 110.

Hinges 230 of the door 200 are hingedly mounted at the mounting member111.

The protective member 112 includes a first hole h1. The protectivemember 112 protects a first cable C1 extending through the first holeh1. The protective member 112 contacts the door 200.

A lighting device 125 to adjust brightness in the showcase is providedin the storage chamber 120. The shelves 130, on which food is placed,are provided in the storage chamber 120.

Power from a branch cable C1′ of the first cable C1 is supplied to thelighting device 125.

The shelves 130 divide the storage chamber 120 into a plurality ofregions. Consequently, food may be placed in the respective regions ofthe storage chamber 120.

The machine compartment 140 is located below the storage chamber 120.

In the machine compartment 140 are provided a compressor 141 to compressa refrigerant, a condenser 142 to condense the high-temperature,high-pressure refrigerant, compressed by the compressor 141, a coolingfan 143 to cool hot air generated from the compressor 141 and thecondenser 142 and enable air around the condenser 142 to beheat-exchanged, a valve 144 disposed between the condenser 142 and anevaporator 151 so as to be opened or closed based on temperature of thestorage chamber 120, a first power supply unit 145 connected to anexternal commercial power source to convert power from the commercialpower source into drive power to be used by components and to supply theconverted power to the components, and a cover 146 to cover the machinecompartment 140.

The cool air generating compartment 150 is located above the storagechamber 120.

In the cool air generating compartment 150 are provided an evaporator151 to perform heat exchange with air in the storage chamber 120 and ablowing fan 152 to blow cool air, heat-exchanged by the evaporator 151,to the storage chamber 120.

When the valve 144 is opened, the refrigerant from the condenser 142 issupplied to the evaporator 151. At this time, the low-temperature liquidrefrigerant is changed into a gaseous refrigerant, thus absorbing latentheat. That is, the evaporator 151 performs a cooling operation. As aresult, ambient air and air in the storage chamber 120 are cooled. Thatis, the evaporator 151 lowers the temperature in the storage chamber120.

The cool air generating compartment 150 further includes a duct 153along which cool air flows.

The duct 153 is provided at the rear of the main body 110. In addition,the evaporator 151 and the blowing fan 152 may be mounted in the duct153 provided at the rear of the main body 110.

A plurality of holes is formed at a wall between the duct 153 and thestorage chamber 120. Cool air flows between the duct 153 and the storagechamber 120 through the holes.

The door 200, as the display module, is hingedly mounted at a frontopening 113 of the main body 110, corresponding to the storage chamber120, to isolate the storage chamber 120 from the outside, therebypotentially preventing leakage of cool air from the storage chamber 120.

The door 200 opens and closes the storage chamber 120. That is, anadministrator, a user or a customer may open the door 200 to put or drawfood into or from the storage chamber 120.

As shown in FIG. 3, the door 200, as the display module, includes atransparent display panel 210, a frame 220 to fix the transparentdisplay panel 210 and a drive module 250 mounted in a predeterminedspace between the frame 220 and a packing 240 to control driving of thetransparent display panel 210.

The transparent display panel 210 is mounted in the frame 220. Thetransparent display panel 210 may be partially or wholly mounted in theframe 220.

The door 200, as the display module, further includes hinges 230provided at the upper and lower ends of one side of the frame 220 sothat the hinges 230 are mounted in the mounting member 111 of the mainbody 110 to hingedly fix one side of the door 220 to the main body 110and a packing 240 mounted in the frame 220 at a side contacting thefront of the main body to absorb impact generated between the door andthe main body 110 and improve a seal between the door and the storagechamber 120 when the door 200 is closed. That is, the drive module 250is protected from external impact by the frame 220 and the packing 240.

The door 200, as the display module, will be described in detail withreference to FIGS. 4A to 4D, 5 and 6.

As shown in FIG. 4A, the frame 220 includes a plurality of frame members221 and 222. The frame members 221 and 222 are separately coupled toeach other.

The packing 240 is detachably mounted to one of the frame members 221and 222, i.e. the frame member 222 contacting the showcase 100, as thesystem body.

Each of the frame members 221 and 222 has a hole 223. The transparentdisplay panel 210 is disposed in the holes 223. That is, the frame 220is disposed at the outside of the transparent display panel 210 toconstitute the edge of the door, as the display module.

In each of the frame members 221 and 222 is provided a plurality ofsupport members 224 to support the transparent display panel 210.

More specifically, the transparent display panel 210 is fitted betweenthe frame members 221 and 222, and the frame members 221 and 222 arecoupled to fix the transparent display panel 210 to the frame 220. Atthis time, the support members 224 support sides of the transparentdisplay panel 210. Also, the frame members 221 and 222 are coupled toeach other by the support members 224.

As shown in FIG. 4B, the transparent display panel 210 is fitted in theframe 220. Consequently, the thickness D1 of the transparent displaypanel 210 of the door, as the display module, is less than the thicknessD2 of the frame 220.

As shown in FIG. 4C, the surface area of the front of the door 200, asthe display module, includes the surface area A1 of the transparentdisplay panel 210 and the surface area A2 of the frame 220. The surfacearea A1 of the transparent display panel 210 is greater than the surfacearea A2 of the frame 220.

The width W1 of the frame at one side where the drive module 250 ismounted may be greater than the width W2 of the frame at the other sidesto easily and safely mount the drive module 250 in the frame.

The transparent display panel 210 may be a liquid crystal display (LCD)or an organic light emitting diodes (OLED). Hereinafter, the LCD, as thetransparent display panel 210, will be described.

As shown in FIG. 4D, the transparent display panel 210 includes a lightguide plate 211, a first polarizing plate 212, a liquid crystal panel213, a second polarizing plate 214, a first sheet 215 and a second sheet216.

A light source is disposed at one side of the light guide plate 211.

The light source may be a cold cathode fluorescent lamp (CCFL), anexternal electrode fluorescence lamp (EEFL), a light emitting diodearray, the light device 125 in the storage chamber 120 or natural light.

Light emitted from the light source is circular polarized lightincluding a left circular polarized light component and a right circularpolarized light component.

The light guide plate 211 enables light emitted from the light source tobe incident upon the first polarizing plate 212. The light guide plate211 includes first and second refraction layers (not shown). The secondrefraction layer is made of a medium having a greater refractive indexthan the first refraction layer. Consequently, light emitted from thelight source is fully reflected by the light guide plate 211, and thefully reflected light is incident upon the first polarizing plate 212.

The light guide plate 211 enables natural light to be incident upon theliquid crystal panel 213 through the first refraction layer and thesecond refraction layer.

The first and second polarizing plates 212 and 214 include cholestericliquid crystals (not shown). The cholesteric liquid crystals of thefirst and second polarizing plates 212 and 214 include a plurality ofcholesteric liquid crystal molecules.

The cholesteric liquid crystal molecules have a left-handed helixstructure and a right-handed helix structure. The left circularpolarized light component is transmitted and the right circularpolarized light component is reflected by the cholesteric liquid crystalmolecules of the left-handed helix structure.

Also, the left circular polarized light component is reflected, and theright circular polarized light component is transmitted, by thecholesteric liquid crystal molecules of the right-handed helixstructure.

Consequently, polarized light transmitted by the first polarizing plate212 becomes a P wave and polarized light reflected by the firstpolarizing plate 212 becomes an S wave.

Meanwhile, the S wave, reflected by the first polarizing plate 212, isincident upon the light guide plate 211 and is reflected by the secondrefraction layer of the light guide plate 211. At this time, thereflected light is converted into a P wave, which may be transmitted bythe first polarizing plate 212. Therefore, the first polarizing plate212 may function as a reflection plate.

The liquid crystal panel 213 includes a thin film transistor, as aswitching element, a first substrate having a pixel electrodeelectrically connected to the thin film transistor, black matricesarranged at a predetermined interval to block light incident from thelight source, a color filter pattern formed between the black matrices,a second substrate having an overcoat layer formed on the color filterpattern and a liquid crystal layer disposed between the first substrateand the second substrate.

The liquid crystal panel 213 adjusts light transmissivity of liquidcrystal cells based on image information transmitted from a controller253 to form an image.

The liquid crystal panel 213 may transmit the P wave incident from thefirst polarizing plate 212 according to the driving of the liquidcrystal cells. That is, the amount of light transmitted is adjustedaccording to the driving of the liquid crystal cells of the liquidcrystal panel 213 to display an image having gradation.

More specifically, the phase of the P wave varies according to thedriving of the liquid crystal panel. When the phase of the P wave ischanged to 90 degrees, the maximum amount of light is transmitted by thesecond polarizing plate 214 to achieve white gradation. When the phaseof the P wave is changed to 45 degrees, less light is transmitted by thesecond polarizing plate 214 to achieve middle gradation.

Consequently, the displacement of the liquid crystals varies based onthe intensity of an electric field applied to the liquid crystal cellsof the liquid crystal panel 213, and the phase of the P wave varies from0 degrees to 90 degrees based on such displacement to achieve desiredgradation.

The second polarizing plate 214 is provided at one side of the liquidcrystal panel 213. The second polarizing plate 214 has an optical axisperpendicular to the first polarizing plate 212. Therefore, the amountof light transmitted is adjusted based on the phase of the polarizedlight of the first polarizing plate 212 varied according to the drivingof the liquid crystal cells of the liquid crystal panel 213.

Consequently, a user or a customer may view food placed in the storagechamber 120 while viewing advertisement or food information regardingthe transparent display panel 210.

The first sheet 215 is a heat insulation sheet provided at the side ofthe transparent display panel 210 adjacent to the storage chamber 120,i.e. one side of the light guide plate 211. The first sheet 215 preventstemperature in the storage chamber 120 from being increased by heatgenerated during driving of the transparent display panel 210.

The second sheet 216 is an anti-reflective coating film provided at theexposed side of the transparent display panel 210, i.e. one side of thesecond polarizing plate 214. The second sheet 216 prevents light frombeing reflected so that the interior of the storage chamber 120 and theimage on the transparent display panel 210 are easily visible from theside of the showcase even on a bright day.

Another example of the transparent display panel will be brieflydescribed.

In this example, a first polarizing plate of the transparent displaypanel is provided at one side of a light guide plate. The transparentdisplay panel includes a first polarizing plate to polarize lightemitted from the light source, a light guide plate provided at one sideof the first polarizing plate to discharge the polarized light incidentthrough the first polarizing plate to the front, a liquid crystal panelprovided at the front of the light guide plate to display an image basedon light incident from the light guide plate, and a second polarizingplate provided at the front of the liquid crystal panel.

The first polarizing plate is located at one side of the light guideplate adjacent to the light incident plane of the light guide plate. Thefirst polarizing plate transmits only the first polarized light of thelight including the first and second polarized lights.

The second polarizing plate has an optical axis perpendicular to thefirst polarizing plate. Therefore, the amount of light transmitted isadjusted based on the phase of the first polarized light of the firstpolarizing plate varied according to the driving of liquid crystal cellsof the liquid crystal panel. For example, when the phase of the firstpolarized light is 0 degrees, the first polarized light is nottransmitted by the second polarizing plate. As the phase of the firstpolarized light is increased, a larger amount of the first polarizedlight is transmitted by the second polarizing plate. That is, greatergradation is achieved as the phase of the first polarized light isincreased.

Both first and second polarized lights of natural light are incidentupon the liquid crystal panel.

When the liquid crystal cells of the liquid crystal panel are notdriven, therefore, the second polarized light of the natural light istransmitted through the liquid crystal panel. When the liquid crystalcells of the liquid crystal panel are driven, the first polarized lightof the natural light is transmitted through the liquid crystal panel.

Consequently, the liquid crystal panel is kept transparent by thenatural light irrespective of whether the liquid crystal panel is drivenor not.

That is, the transparent display panel 210 remains transparent to thenatural light irrespective of a display driving command. Consequently, auser or a customer may view food placed in the storage chamber 120 atany time.

The transparent display panel 210 displays advertisements, foodinformation and user-tailored information in response to a command fromthe controller 253 provided in the drive module 250.

The drive module 250 is at least one printed circuit board (PCB). In thedrive module 250 are provided a second power supply unit 252 to convertpower from the first power supply unit 145 into drive power of acommunication unit, drive power of the controller and drive power of adisplay drive unit, a communication unit 252 to receive data transmittedfrom a server, a controller 253 to process the received data and outputa drive command corresponding to the processed data and a display driveunit 254 to drive the transparent display panel in response to thecommand from the controller so that data are displayed on thetransparent display panel.

The second power supply unit 252 is connected to the first power supplyunit 145 of the main body 110 via the first cable C1 to receive powerfrom the first power supply unit 145.

The first cable C1 is located at the system body 100 and the door 200.That is, the first cable C1 extends from the system body 100 to the door200.

Extension of the cable between the main body 110 and the door 200 willbe described with reference to FIGS. 5 and 6.

As shown in FIG. 5, the packing 240 of the door 200 includes a secondhole h2.

The second hole h2 of the packing 240 is located at a position where theprotective member 112 of the main body 110 contacts the packing 240.Also, the main body 110 includes a hole formed at a positioncorresponding to the hole h1 of the protective member 112.

In this structure, the cable C1, connected to the first power supplyunit 145, extends to the second power supply unit 251 of the door 200through the first hole h1 of the protective member 112 of the main body110 and the second hole h2 of the packing 240 of the door 200.

In addition, the second hole h2 formed at the packing 240 of the door200 may be formed at the frame 220 of the door 200.

Another example is shown in FIG. 6.

As shown in FIG. 6, the hinge 230 is provided at each of the upper andlower ends of the frame 220 of the door 200. The hinge 230 is hingedlymounted at the mounting member 111 of the main body 110 so that one sideof the door 200 is hingedly fixed to the main body 110.

That is, the door 200 is hingedly mounted to the main body 110 by thehinges 230.

A first hole h3 is formed at the mounting member 111 of the main body110, and a second hole h4 is formed at the hinge 230 of the door 200.The second hole h4 extends to the frame 220 of the door 200.

In addition, the main body 110 includes a hole corresponding to thefirst hole h3 of the mounting member 111, and the frame 220 of the door200 includes a hole corresponding to the second hole h4 of the hinge230.

In this structure, the cable C1, connected to the first power supplyunit 145, extends to the second power supply unit 251 of the door 200through the first hole h3 of the mounting member 111 of the main body110 and the second hole h4 of the hinge 230 of the door 200.

FIG. 7 is a control block diagram of the display module provided in thedisplay system according to the exemplary embodiment of the presentinvention. The display module includes a second power supply unit 251, acommunication unit 252, a controller 253 and a display drive unit 254.

The second power supply unit 251, the communication unit 252, thecontroller 253 and the display drive unit 254 are provided in the drivemodule 250 disposed in the frame 220 of the door 200, as the displaymodule.

The second power supply unit 251 is connected to the first power supplyunit 145 of the main body 110 via the first cable C1 to receive powerfrom the first power supply unit 145, to covert the received power intodrive power of the controller, drive power of the controller and drivepower of the display drive unit, and to supply the converted power tothe communication unit 252, the controller 253 and the display driveunit 254.

The second power supply unit 251 performs AC/DC conversion and DC/DCconversion.

The communication unit 252 receives data from a server or a terminal andtransmits the received data to the controller 253. The communicationunit 252 performs wired and/or wireless communication.

Data may include advertisement image data, food data, such as date ofmanufacture, expiry date, nutritional information and place of origin,event information, discount coupon image data and image data related tothe surroundings of the showcase. Such image data may include pictures,photographs, words and video.

In addition, the server communicates with the communication unit 252through wired and/or wireless communication. The terminal communicateswith the communication unit 252 through wireless communication, such asWiFi or Bluetooth.

Also, the terminal may be an administrator terminal which directlycontrols driving of the transparent display panel 210.

If the terminal is a smart phone, an application to control the displayof the showcase is installed in the smart phone. This application may bedownloaded from an app store, which is an application store, or theserver. Also, the application may be upgraded and updated.

The controller 253 processes the received data and outputs a drivecommand corresponding to the processed data to the display drive unit254. At this time, the controller 253 receives data in a predeterminedformat and decodes the received data.

The display drive unit 254 drives the transparent display panel inresponse to a command from the controller so that data are displayed onthe transparent display panel.

The display drive unit 254 drives the liquid crystal cells of the liquidcrystal panel 213 in response to the command from the controller 253 sothat an image is displayed on the transparent display panel 210 and thetransparency of the transparent display panel is adjusted.

The display module may further include a storage unit to store data andan input unit to allow data received by the communication unit or storedin the storage unit to be selected.

At this time, the controller confirms the data selected through theinput unit, processes the confirmed data, and transmits a drive commandcorresponding to the processed data to the display drive unit 254.

In a case in which a plurality of data is stored in the storage unit,the controller 253 may control one of the data to be displayed or thedata to be sequentially displayed at a predetermined interval.

The data stored in the storage unit are transmitted from the serverand/or the terminal. The data may be stored in a compressed file format.

FIG. 8 is a control block diagram of a display system according toanother exemplary embodiment of the present invention. The displaysystem includes a second power supply unit 251, a communication unit252, a controller 253, a display drive unit 254, a sound drive unit 255,a storage unit 256, an input unit 260, a recognition unit 270 and adetection unit 280.

The second power supply unit 251, the communication unit 252, thecontroller 253, the display drive unit 254, the sound drive unit 255 andthe storage unit 256 may be provided in a drive module.

The input unit 260, the recognition unit 270 and the detection unit 280may also be provided in the drive module 250. Alternatively, the inputunit 260, the recognition unit 270 and the detection unit 280 may beprovided in a frame and may be then electrically connected to thecontroller 253 of the drive module 250.

The second power supply unit 251 is connected to the first power supplyunit 145 of the main body 110 via the first cable C1 to receive powerfrom the first power supply unit 145, to covert the received power intodrive power to be used by components and to supply the converted powerto the communication unit 252, the controller 253, the display driveunit 254, the sound drive unit 255, the storage unit 256, the input unit260, the recognition unit 270 and the detection unit 280.

The second power supply unit 251 performs AC/DC conversion and DC/DCconversion.

The communication unit 252 communicates with a server or a terminal,such as a smart phone, receives image data and/or sound data from theserver or the terminal and transmits the received data to the controller253. The communication unit 252 performs wired and/or wirelesscommunication.

In addition, the server communicates with the communication unit 252through wired and/or wireless communication. The terminal communicateswith the communication unit 252 through wireless communication, such asWiFi or Bluetooth.

Also, the terminal may be an administrator terminal which directlycontrols driving of the transparent display panel 210.

If the terminal is a smart phone, an application to control the displayof the showcase is installed in the smart phone. This application may bedownloaded from an app store, which is an application store, or theserver. Also, the application may be upgraded and updated.

The communication unit 252 may communicate with a customer terminalthrough wireless communication such as WiFi or Bluetooth. At this time,the communication unit 252 transmits the name and identification of acustomer received from the customer terminal to the controller 253.Also, the communication unit 252 transmits a tailored informationdisplay approval signal received from the customer terminal to thecontroller 253.

The controller 253 processes data received by the communication unit 252and outputs a drive command corresponding to the processed data to thedisplay drive unit 254. At this time, the controller 253 receives datain a predetermined format and decodes the received data.

Also, the controller 253 processes data stored in the storage unit 256and outputs a drive command corresponding to the processed data to thedisplay drive unit 254.

As shown in FIG. 9, the controller 253 includes a first signalprocessing unit 253 a to process the data received by the communicationunit 252, a second signal processing unit 253 b to process the datastored in the storage unit, and a display controller 253 c to create andoutput a drive command to display the data processed by the first signalprocessing unit and the second signal processing unit.

The first signal processing unit may include a signal processing unit toprocess data received through wired communication and a signalprocessing unit to process data received through wireless communication.

The second signal processing unit 253 b may encode data when the dataare stored in the storage unit.

In addition, the controller 253 and the first and second signalprocessing units may be separately provided. In this case, the firstsignal processing unit and the second signal processing unit transmitprocessed data to the controller 253.

The display drive unit 254 drives the transparent display panel inresponse to a command from the controller so that data are displayed onthe transparent display panel.

The display drive unit 254 drives the liquid crystal cells of the liquidcrystal panel 213 in response to the command from the controller 253 sothat an image is displayed on the transparent display panel 210 and thetransparency of the transparent display panel is adjusted.

Also, display drive unit 254 outputs reversed data in response to thecommand from the controller 253 so that a reversed image is displayed onthe transparent display panel 210.

The sound drive unit 255 outputs sound corresponding to an imagedisplayed on the transparent display panel 210 through a speaker inresponse to a command from the controller 253.

For example, when an advertisement image is displayed on the transparentdisplay panel 210, the sound drive unit 255 outputs sound correspondingto the advertisement or sound requesting that the door be closed througha speaker.

The storage unit 256 stores data transmitted from the server or theterminal. At this time, the data may be stored in a compressed fileformat.

The storage unit 256 stores customer information corresponding to nameand identification for each customer. The customer information includestailored information, such as date of purchase, purchase quantity foreach article, purchase content and consumption patterns, identification,customer terminal information and customer personal information. Thetailored information is transmitted from the terminal.

The storage unit 256 stores information regarding food stored in thestorage chamber 120. The food information includes date of manufacture,expiry date, place of origin, calories, nutritional information, companyname and an advertisement image.

The controller 253 controls driving of the display drive unit 254 andthe sound drive unit 255 based on a signal input from the input unit260, the recognition unit 270 or the detection unit 280.

A control configuration between the controller 253 and the input unit260 will be described in more detail.

The input unit 260 includes a power mode button to turn power on andoff, a first mode button to display an advertisement image, a secondmode button to display an information regarding food stored in thestorage chamber 120, a third mode button to adjust the transparency ofthe transparent display panel, and an update mode button (not shown) toupdate image information stored in the storage unit 256.

The input unit 260 transmits a button signal input by a user to thecontroller 253.

The controller 253 controls driving of the display drive unit 254 basedon the button signal transmitted from the input unit 260.

More specifically, when an input signal of the power mode button istransmitted while power is supplied to the transparent display panel,the controller 253 controls an image not to be displayed on thetransparent display panel so that the transparent display panel is kepttransparent. When an input signal of the power mode button istransmitted while supply of power to the transparent display panel isinterrupted, the controller 253 controls an image to be displayed on thetransparent display panel so that advertisement or food information isdisplayed on the transparent display panel. At this time, a mode beforepower is turned off is performed or a predetermined mode is performedwhen power is turned on.

When an input signal of the first mode button is transmitted, thecontroller 253 controls an advertisement image to be displayed on thetransparent display panel. When an input signal of the second modebutton is transmitted, the controller 253 controls a food informationimage to be displayed on the transparent display panel. When an inputsignal of the third mode button is transmitted, the controller 253adjusts transparency of the transparent display panel.

In addition, the storage unit 256 stores image information for eachmode.

A control configuration between the controller 253 and the recognitionunit 270 will be described in more detail.

The recognition unit includes a tag recognition unit to recognize tagsand/or a code recognition unit to recognize a bar code or a quickresponse (QR) code.

The tag recognition unit is a radio frequency identification (RFID)recognition unit to recognize data stored in RFID tags using radiofrequency. The tag recognition unit recognizes data in a tag (not shown)attached to a customer membership card and transmits the recognized datato the controller 253.

The code recognition unit scans a bar code or a QR code provided on foodand transmits the scanned data to the controller 253.

The controller 253 confirms name and identification (ID) of a customerbased on the data of the tag transmitted from the recognition unit 270and controls the display drive unit 254 to display the tailoredinformation of the customer.

More specifically, the controller 253 confirms the name and ID of thecustomer in the tag and controls an image, such as a welcome message, aswell as the name or nickname of the customer to be displayed on thetransparent display panel, retrieves customer information coincidingwith the confirmed ID from the storage unit 256, and controls tailoredinformation of the retrieved customer to be displayed on the transparentdisplay panel.

The tailored information of the customer includes date of purchase,purchase content, purchase quantity for each article and consumptionpatterns during a predetermined period of time, which are provided toimprove customer satisfaction.

In addition, the controller 253 may communicate with the customerterminal based on the data in the tag, and, when a tailored informationdisplay approval signal is transmitted from the customer terminal, maycontrol the tailored information to be displayed on the transparentdisplay panel.

During communication with the customer terminal, the controller 253 mayretrieve customer terminal information stored in the storage unit 256based on the customer ID and may communicate with the customer terminalbased on the retrieved information.

Also, the controller 253 may communicate with the customer terminal totransmit the tailored information to the customer terminal.

Also, the controller 253 may communicate with the customer terminal toacquire the name and ID of the customer and control driving of thedisplay drive unit 254 based on the acquired name and ID of thecustomer.

The controller 253 confirms information regarding corresponding foodbased on the scanned date of the bar code or the QR code and determineswhether the confirmed food information is stored in the storage unit256. When the information regarding the corresponding food is stored inthe storage unit 256, the controller 253 transmits the informationregarding the corresponding food to the storage unit 256 so that theinformation regarding the food is stored in the storage unit 256.

Also, when the information regarding the corresponding food is stored inthe storage unit 256, the controller 253 updates the informationregarding the corresponding food stored in the storage unit 256. Inaddition, when the information regarding the food stored in the storageunit 256 coincides with the scanned information, the controller 253 maycontrol the information regarding the food stored in the storage unit256 to be maintained.

When additional food is placed in the showcase, information regardingthe additionally placed food is updated using the code recognition unit,thereby potentially allowing the managing of information regarding foodplaced in the showcase.

Also, the controller 253 determines whether an advertisement image ofcorresponding food is stored in the storage unit 256 based on thescanned data of the food. When the advertisement image of thecorresponding food is stored in the storage unit 256, the controller 253controls the advertisement image of the corresponding food to bedisplayed.

An advertisement image display sequence of the additionally placed foodis decided in consideration of a predetermined advertisement sequence.Alternatively, the advertisement image display sequence of theadditionally placed food may be decided by an administrator.

Also, the controller 253 may determine whether image information ofcorresponding food is present in the scanned data of the food. When theimage information regarding the corresponding food is present in thescanned data of the food, the controller 253 may control the imageinformation to be displayed as an advertisement image of thecorresponding food.

A control configuration between the controller 253 and the detectionunit 280 will be described in more detail.

The detection unit 280 includes a human body detection unit to detect ahuman body and/or a door opening and closing detection unit to detectopening and closing of the door.

The controller 253 adjusts transparency and/or brightness of thetransparent display panel based on the determination as to whether thehuman body has been detected, controls reversal of an image based on thedetermination as to whether the door has been opened or closed, andcontrols change of the image based on time for which the door is open.

A control configuration between the human body detection unit and thecontroller will now be described.

The human body detection unit detects whether a human body is present.The human body detection unit may include a thermal infrared sensor todetect heat generated from a human body, a motion sensor to detectmotion of a human body, a load sensor to detect weight applied to ahuman body. Hereinafter, the thermal infrared sensor, as the human bodydetection unit, will be described.

The thermal infrared sensor detects thermal infrared radiation aroundthe showcase and transmits the detected heat to the controller 253.

The controller 253 determines whether a person is adjacent to theshowcase based on the thermal infrared rays. Upon determining that aperson is adjacent to the showcase, the controller 253 controls thedisplay drive unit 254 to adjust transparency or brightness of thetransparent display panel 210.

For example, when a person is adjacent to the showcase, the transparencyof the transparent display panel 210 is increased so that the foodplaced in the storage chamber 120 is more visible. Otherwise, thebrightness of the transparent display panel 210 is increased so that animage displayed on the transparent display panel 210 is more clearlyvisible. On the other hand, the brightness of the transparent displaypanel 210 may be decreased, when no person is adjacent to the showcase,to reduce power consumption.

Also, upon determining that a person is adjacent to the showcase, thecontroller 253 may control an image displayed on the transparent displaypanel 210 to be changed.

For example, only an unmovable image may be displayed on the transparentdisplay panel 210, and, upon determining that a person is adjacent tothe showcase, video may be displayed to draw person's attention.

A control configuration between the door opening and closing detectionunit and the controller will be described.

The door opening and closing detection unit detects whether the door hasbeen opened or closed. The door opening and closing detection unit mayinclude a temperature sensor, an infrared sensor, an ultrasonic sensor,a hall sensor or a micro switch.

When the door 200 is opened, the controller 253 controls reverse drivingof the display driving unit 254 so that an image displayed on the closeddoor is viewed by a customer, counts an open time of the door 200, andcontrols the display drive unit 254 to display a message indicating thatit is difficult to keep food fresh due to discharge of cool air or amessage requesting that the door 200 be closed when the counted opentime of the door exceeds a reference time.

The controller 253 may determine whether a message is present in thecurrently displayed image based on the currently displayed imageinformation and may not perform reverse control when no message ispresent in the currently displayed image.

The storage unit 256 stores image information for each mode and reverseimage information of each image, a reference open time of the door 200to efficiently control cool air in the storage chamber for freshness offood, and image information including a message requesting that the doorbe closed based on an elapsed door open time.

As shown in FIG. 10, a user or a customer may correctly view a writtenimage ‘B’ from the outside of the door when the door 200 is closed.Also, when the door 200 is opened, the written image displayed on thedoor 200 is reversed so that the user or the customer may correctly viewthe written image ‘B’ from the inside of the door.

An example of door opening and closing detection using the temperaturesensor and display control of the transparent display panel will bedescribed.

The temperature sensor detects temperature in the storage chamber 120and transmits the detected temperature to the controller 253.

The controller 253 monitors temperature in the storage chamber 120 andcalculates a change rate of the temperature in the storage chamber 120.When the change rate of the temperature in the storage chamber 120exceeds a reference change rate, the controller 253 determines that thedoor 200 is open. Upon determining that the door 200 is open, thecontroller 253 may control the image displayed on the transparentdisplay panel 210 to be reversed.

The controller 253 may estimate a door open time based on the change ofthe temperature in the storage chamber 120.

While the door remains open, the temperature in the storage chamber 120is maintained within a reference temperature range. When the door isclosed, heat exchange is not performed between cool air in the storagechamber and external air with the result that the temperature in thestorage chamber 120 is lowered below the reference temperature range.

The reference temperature range is an average temperature range in thestorage chamber when the door is opened.

The controller 253 may compare a door open time with a reference timeand, when the door open time exceeds the reference time, may control theimage displayed on the transparent display panel 210 to be changed.

For example, the transparent display panel 210 may display an imagerequesting that the door be closed, and the speaker may output soundrequesting that the door be closed.

An example of door opening and closing detection using the infraredsensor and display control of the transparent display panel will bedescribed.

The infrared sensor includes a light emitting unit provided at the mainbody 110 and a light receiving unit provided in the door 200. When thedoor is opened, the infrared sensor drives the light emitting unit inresponse to a command from the controller 253, detects light emittedfrom the light emitting unit through the light receiving unit, andtransmits the detected light to the controller 253. When the door isclosed, the light emitting unit is not driven with the result that lightis not detected.

The amount of light detected by the light receiving unit decreases asthe distance between the door 200 and the main body 110 is increased asthe result of opening of the door 200 and increases as the distancebetween the door 200 and the main body 110 is decreased as the result ofclosing the door 200. That is, a door opening angle may be estimatedbased on the amount of light. Also, a door open time may be estimatedbased on a light amount detection time.

The controller 253 confirms a door opening angle based on the amount oflight detected by the infrared sensor and determines whether the dooropening angle exceeds a reference angle. When the door opening angleexceeds the reference angle, the controller 253 controls an imagedisplayed on the transparent display panel 210 to be reversed.

Also, the controller 253 counts a door open time based on a lightdetection time. When the counted door open time exceeds a referencetime, the controller 253 controls the image displayed on the transparentdisplay panel 210 to be changed. The changed image requests that thedoor be closed.

An example of door opening and closing detection using the ultrasonicsensor and display control of the transparent display panel will bedescribed.

The ultrasonic sensor includes an oscillation unit provided in the mainbody 110 and a receiving unit provided in the door 200. When the door isopened, the ultrasonic sensor drives the oscillation unit in response toa command from the controller 253, detects ultrasonic waves oscillatedfrom the oscillation unit through the receiving unit, and transmits thedetected ultrasonic waves to the controller 253. When the door isclosed, the oscillation unit is not driven with the result thatultrasonic waves are not detected.

Arrival time of ultrasonic waves detected by the receiving unitincreases as the distance between the door 200 and the main body 110 isincreased as the result of opening of the door 200 and decreases as thedistance between the door 200 and the main body 110 is decreased as theresult of closing the door 200. That is, a door opening angle may beestimated based on the arrival time of ultrasonic waves. Also, a dooropen time may be estimated based on determination as to whetherultrasonic waves are detected.

The controller 253 compares an ultrasonic wave oscillation time with adetection time to calculate an ultrasonic wave arrival time, confirms adoor opening angle based on the calculated ultrasonic wave arrival timeand determines whether the door opening angle exceeds a reference angle.When the door opening angle exceeds the reference angle, the controller253 controls an image displayed on the transparent display panel 210 tobe reversed.

Also, the controller 253 counts a door open time based on determinationas to whether ultrasonic waves are detected. When the counted door opentime exceeds a reference time, the controller 253 controls the imagedisplayed on the transparent display panel 210 to be changed. Thechanged image requests that the door be closed.

An example of door opening and closing detection using the hall sensorand display control of the transparent display panel will be described.

The hall sensor 191 detects voltage generated based on the intensity ofa magnetic field. The hall sensor is provided in the main body 110around the hinge 230. When a drive command is transmitted from thecontroller 253 when the door is opened, the hall sensor 191 detectsvoltage generated by protrusions 231 to 235 of the hinge 230 andtransmits the detected voltage to the controller 253.

As shown in FIG. 11( a), the hinge 230 includes a plurality ofprotrusions 231 to 235. The protrusions 231 to 235 have different sizes.

When the door is opened, the hinge fixed to the frame of the door isrotated. At this time, the protrusions of the hinge are also rotated.

That is, the protrusions adjacent to the hall sensor 191 are changed asthe door 200 is rotated. At this time, the distances between therespective protrusions and the hall sensor 191 differ with the resultthat different voltages for the respective protrusions are detected bythe hall sensor.

At this time, the hall sensor detects voltage proportional to theintensity of a magnetic field generated at each protrusion and transmitsthe detected voltage to the controller 253.

When the door 200 is formed so as to be rotated in the clockwisedirection and the protrusions 231 to 235 of the hinge 230 are formed sothat the size of the protrusions 231 to 235 decreases in the clockwisedirection, as shown in FIG. 11( a), the size of the protrusions facingthe hall sensor 191 provided in the main body 110 gradually increases asthe opening angle of the door 200 is increased. At this time, thedistance between the hall sensor 191 and the protrusion is decreasedwith the result that the intensity of a magnetic field is increased, andtherefore, voltage is also increased.

FIG. 11( b) illustrates the distance d1 between the hall sensor 191 andthe protrusion 231 when the door is closed, and FIG. 11( c) illustratesthe distance d2 between the hall sensor 191 and the protrusion 233 whenthe door is opened 135 degrees. That is, the distance between the hallsensor and the protrusion is decreased when the door is opened.

The controller 253 confirms a door opening angle corresponding to thevoltage detected by the hall sensor 191 based on the voltage for eachprotrusion pre-stored in the controller 253 and estimates a door opentime based on the detected voltage.

The controller 253 compares a door opening angle with a reference angle.When the door opening angle exceeds the reference angle, the controller253 controls an image displayed on the transparent display panel 210 tobe reversed.

Also, the controller 253 determines whether the door is closed based onthe detected voltage. Upon determining that the door is closed, thecontroller 253 controls the hall sensor 191 not to be driven. When thedoor is opened, the controller 253 counts a door open time. When thecounted door open time exceeds a reference time, the controller 253controls an image displayed on the transparent display panel 210 to bechanged. The changed image requests that the door be closed.

When the door is closed, the micro switch is turned on. When the door isopened, the micro switch is turned off.

That is, an off signal is transmitted from the micro switch, thecontroller 253 determines that the door is opened and counts an off timeof the micro switch to estimate a door open time.

When the door is opened, the controller 253 controls an image displayedon the transparent display panel 210 to be reversed and compares thedoor open time with a reference time. When the door open time exceedsthe reference time, the controller 253 controls an image requesting thatthe door be closed to be displayed.

FIG. 12 is a view illustrating the structure of a transparent displaypanel of a display module provided in a display system according toanother exemplary embodiment of the present invention. In this exemplaryembodiment, a showcase further includes a transparent touch displaypanel unlike the showcase according to the previous exemplaryembodiment.

The transparent touch display panel is a combination of a transparentdisplay panel and a touch panel. The transparent touch display panelincludes a light source, a light guide plate 211, a first polarizingplate 212, a liquid crystal panel 213, a second polarizing plate 214, afirst sheet 215, a second sheet 216, a touch panel 217 and lightemitting element and light receiving element arrays 218.

Components of the showcase according to this exemplary embodiment areidentical to those of the showcase according to the previous exemplaryembodiment excluding the transparent touch display panel and a drivemodule, and therefore, a description thereof will be omitted.

The light source, the light guide plate 211, the first polarizing plate212, the liquid crystal panel 213 and the second polarizing plate 214 ofthe transparent touch display panel 210 shown in FIG. 12 are identicalto those shown in FIG. 7, and therefore, a description thereof will beomitted.

The first sheet 215 is a heat insulation sheet provided at the side ofthe transparent touch display panel 210 adjacent to the storage chamber120, i.e. one side of the light guide plate 211. The first sheet 215prevents temperature in the storage chamber 120 from being increased byheat generated during driving of the transparent touch display panel210.

The second sheet 216 is an anti-reflective coating film provided at theexposed side of the transparent touch display panel 210, i.e. one sideof the touch panel 217. The second sheet 216 prevents light from beingreflected so that the interior of the storage chamber 120 and an imageon the transparent display panel 210 are easily visible from the side ofthe showcase even on a bright day.

The touch panel 217 may include a resistive touch panel, a capacitivetouch panel, an ultrasonic touch panel and an infrared touch panel. Inthis exemplary embodiment, an infrared touch panel will be described.

The touch panel 217 is transparent. The touch panel 217 transmits animage displayed on the liquid crystal panel. Consequently, a person mayview the image displayed on the liquid crystal panel through the touchpanel 217.

The touch panel 217 is flexible. When a finger of a person or an inputunit, such as a pen, contacts the touch panel 217, therefore, the touchpanel 217 may be flexibly depressed.

The touch panel 217 is hexahedral. The light emitting element and lightreceiving element arrays 218 are provided at sides of the touch panel.

One of the light emitting element arrays is disposed in the X-axisdirection, and the other light emitting element array is disposed in theY-axis direction. One of the light receiving element arrays is disposedin the X-axis direction, and the other light receiving element array isdisposed in the Y-axis direction.

Each of the light emitting element arrays includes a plurality of lightemitting elements, which emits light in response to a command from alight drive part of a touch drive unit 257. Each of the light receivingelement arrays includes a plurality of light receiving elements, whichtransmits a light receiving signal to a position detection part of thetouch drive unit 257.

When a hand of a person or an input unit, such as a pen, contacts acertain point of the touch panel 217, light passing through the touchpanel 217 is blocked at at least one light emitting element of the lightemitting element arrays, and at least one light receiving elementcorresponding to the at least one light emitting element does not detectlight. That is, the light receiving elements, having detected light,output a light detection signal to the position detection part of thetouch drive unit 257, and the light receiving elements, having notdetected light, output a light non-detection signal to the positiondetection part of the touch drive unit 257.

The touch panel 217 may be a multi-touch panel.

FIG. 13 is a control block diagram of a display system according toanother exemplary embodiment of the present invention. The displaysystem includes a second power supply unit 251, a communication unit252, a controller 253, a display drive unit 254, a sound drive unit 255,a storage unit 256, a touch drive unit 257, an input unit 260, arecognition unit 270 and a detection unit 280.

The second power supply unit 251, the communication unit 252, thecontroller 253, the display drive unit 254, the sound drive unit 255,the storage unit 256 and the touch drive unit 257 may be provided in adrive module.

The input unit 260, the recognition unit 270 and the detection unit 280may also be provided in the drive module 250. Alternatively, the inputunit 260, the recognition unit 270 and the detection unit 280 may beprovided in a frame and may then be electrically connected to thecontroller 253 of the drive module 250.

The second power supply unit 251 is connected to the first power supplyunit 145 of the main body 110 via the first cable C1 to receive powerfrom the first power supply unit 145, to covert the received power intodrive power to be used by components and to supply the converted powerto the communication unit 252, the controller 253, the display driveunit 254, the sound drive unit 255, the storage unit 256, the touchdrive unit 257, the input unit 260, the recognition unit 270 and thedetection unit 280.

The second power supply unit 251 performs AC/DC conversion and DC/DCconversion.

The communication unit 252 communicates with a server or a terminal,such as a smart phone, receives image data and/or sound data from theserver or the terminal and transmits the received data to the controller253. The communication unit 252 performs wired and/or wirelesscommunication.

In addition, the server communicates with the communication unit 252through wired and/or wireless communication. The terminal communicateswith the communication unit 252 through wireless communication, such asWiFi or Bluetooth.

The controller 253 processes data received by the communication unit 252and outputs a drive command corresponding to the processed data to thedisplay drive unit 254. At this time, the controller 253 receives datain a predetermined format and decodes the received data.

Also, the controller 253 processes data stored in the storage unit 256and outputs a drive command corresponding to the processed data to thedisplay drive unit 254.

The controller 253 controls driving of the display drive unit 254 basedon the position of a touch point detected by the position detection partof the touch drive unit 257.

The controller 253 may control driving of the display drive unit 254based on position information of multi-touch points transmitted from theposition detection part.

More specifically, when position information of the touch point istransmitted, the controller 253 confirms the currently displayed imageinformation, confirms a button present at the position of the touchpoint among buttons included in the confirmed image, and controls a subimage corresponding to the confirmed button to be displayed or performsa function corresponding to the confirmed button.

For example, when an advertisement image having a detailed view button(not shown) and a mode change button is displayed on the transparenttouch display panel 210 and a touch point touched by a customercorresponds to the detailed view button, the controller 253 controlsimage information corresponding to the detailed view button to bedisplayed.

At this time, the transparent touch display panel displays an image ofan advertising object together with the currently displayedadvertisement image or converts the currently displayed advertisementimage into an image of an advertising object and displays the image ofthe advertising object.

The image of the advertising object may include price of the advertisingobject, positions of stores that sell the advertising object, discountinformation of the advertising object and information regarding theplace of origin.

The controller 253 controls a menu button, a mode change button and anupdate button to be basically displayed irrespective of type of imagesdisplayed on the transparent touch display panel.

Alternatively, the controller 253 may control the menu button, the modechange button and the update button not to be displayed on thetransparent touch display panel and may control the menu button, themode change button and the update button to be displayed on thetransparent touch display panel when a certain position is touched by auser.

The controller 253 controls basic buttons, such as the menu button, themode change button and the update button, to be displayed at differentpositions than a main image so that the menu button, the mode changebutton and the update button do not overlap the main image.

When the menu button is touched, the controller 253 controls a subbutton of the menu to be displayed. When the update button is touched,the controller 253 controls communication with a terminal to update datastored in the current storage unit 256. When the mode change button istouched, the controller 253 controls a mode to be changed from thecurrent mode to another mode.

For example, when the current mode is an advertisement image displaymode, the controller 253 controls a mode to be changed from theadvertisement image display mode to an article information image displaymode.

When the showcase is installed in a large-scale supermarket, theshowcase further includes an event information button, a discount couponbutton and an information map button as basic buttons displayed on thetransparent touch display panel.

When the event information button is touched, the controller 253controls an event information image to be displayed. When the discountcoupon button is touched, the controller 253 controls a discount couponimage to be displayed. When the information map button is touched, thecontroller 253 controls an information map image related to thesurroundings of the showcase to be displayed.

In addition, when the discount coupon image is displayed, a customer mayacquire the discount coupon image using his/her terminal and show thecoupon stored in the terminal to a salesperson when the customer wishesto buy a corresponding article to get a discount with respect to thecorresponding article.

The display drive unit 254 and the sound drive unit 255 are identical inconstruction to those of the previous exemplary embodiments, andtherefore, a description thereof will be omitted.

The storage unit 256 stores image information for each mode and reverseimage information of each image, functions of buttons included in aplurality of pieces of image information, positions of buttons for eachpiece of image information, and positions of the respective lightreceiving elements of the light receiving element arrays.

The storage unit 256 stores position information of the menu button, themode change button, the update button, the event information button, thediscount coupon button, and the information map button. Also, thestorage unit 256 stores a sub image of each button.

The storage unit 256 stores data transmitted from the server or theterminal. At this time, the data may be stored in a compressed fileformat.

The storage unit 256 stores customer information corresponding to nameand identification for each customer. The customer information includestailored information, such as date of purchase, purchase quantity foreach article, purchase content and consumption patterns, identification,customer terminal information and customer personal information. Thetailored information is transmitted from the terminal.

The storage unit 256 stores information regarding food stored in thestorage chamber 120. The food information includes date of manufacture,expiry date, the place of origin, calories, nutritional information,company name and an advertisement image.

The controller 253 controls driving of the display drive unit 254 andthe sound drive unit 255 based on a signal input from the input unit260, the recognition unit 270 or the detection unit 280.

The touch drive unit includes a light drive part and a positiondetection part.

The light drive part drives the light emitting element arrays to emitlight in response to a command from the controller 253.

The position detection part recognizes light receiving elements havingtransmitted a light detection signal as 1 and a light receiving elementhaving transmitted a light non-detection signal as 0. The positiondetection part confirms the position of the light receiving elementrecognized as 0, detects the position of a touch point and transmits theposition of the detected touch point to the controller 253.

The position detection part may be capable of multi-touch detection.That is, when a plurality of points is touched, the position detectionpart detects positions of the multiple touch points and transmits thepositions of the detected multiple touch points to the controller 253.

In addition, the controller 253 may control driving of the transparenttouch display panel based on a drive command transmitted from anadministrator terminal. A control configuration between the controller253 and the detection unit 270 of this exemplary embodiment is identicalto that of the previous exemplary embodiments, and therefore, adescription thereof will be omitted.

A control configuration between the controller 253 and the input unit260 will be described.

The input unit 260 includes a power mode button (not shown) to turnpower on and off. The input unit 260 transmits a button signal input bya user to the controller 253.

A control configuration between the controller 253 and the recognitionunit 270 will be described.

The recognition unit includes a tag recognition unit and/or a coderecognition unit.

The tag recognition unit is a radio frequency identification (RFID)recognition unit to recognize data stored in RFID tags using radiofrequency. The tag recognition unit reads data in a tag (not shown)attached to a customer membership card and transmits the read data tothe controller 253.

The code recognition unit may be a bar code recognition unit or a QRcode recognition unit. The code recognition unit scans a code providedon food and transmits the scanned data to the controller 253.

The controller 253 confirms name and ID of a customer based on the dataof the tag transmitted from the tag recognition unit and controls thedisplay drive unit 254 to display the tailored information of thecustomer.

More specifically, the controller 253 confirms the name and ID of thecustomer in the tag and controls an image, such as a welcome message, aswell as the name or nickname of the customer to be displayed on thetransparent display panel, and controls the display drive unit 254 todisplay a message asking a question as to whether tailored informationis to be displayed and yes and no buttons.

The controller 253 confirms the position of a touch point touched by acustomer. When the position of the touch point corresponds to the ‘yes’button, the controller 253 controls the tailored information to bedisplayed. When the position of the touch point corresponds to the ‘no’button, the controller 253 controls the tailored information not to bedisplayed. When the touch point is not recognized within a predeterminedtime after the question is asked, a corresponding operation is ended.

Also, the controller 253 may communicate with the customer terminal toacquire the name and ID of the customer and control driving of thedisplay drive unit 254 based on the acquired name and ID of thecustomer.

The code recognition unit recognizes a bar code or a QR code provided onfood and transmits the recognized data to the controller 253.

The controller 253 confirms information regarding corresponding foodbased on the scanned food data and determines whether informationregarding the confirmed food is stored in the storage unit 256. When theinformation regarding the corresponding food is not stored in thestorage unit 256, the controller 253 transmits the information regardingthe corresponding food to the storage unit 256 so that the informationregarding the food is stored in the storage unit 256.

When the information regarding the corresponding food is stored in thestorage unit 256, the controller 253 controls the display drive unit todisplay a message asking a question as to whether information regardingthe corresponding food is to be updated and yes and no buttons.

The controller 253 confirms the position of a touch point touched by anadministrator. When the position of the touch point corresponds to the‘yes’ button, the controller 253 updates information regarding thecorresponding food stored in the storage unit 256. When the position ofthe touch point corresponds to the ‘no’ button, the controller 253maintains information regarding the corresponding food stored in thestorage unit 256. When the touch point is not recognized within apredetermined time after the question is asked, the controller 253updates information regarding the corresponding food stored in thestorage unit 256.

When additional food is placed in the showcase, information regardingthe additionally placed food is updated using the code recognition unit,thereby potentially allowing the managing of information regarding foodplaced in the showcase.

Also, the controller 253 determines whether an advertisement image ofcorresponding food is stored in the storage unit 256 based on thescanned data of the food. When the advertisement image of thecorresponding food is stored in the storage unit 256, the controller 253controls the advertisement image of the corresponding food to bedisplayed.

Also, the controller 253 may determine whether image information ofcorresponding food is present in the scanned data of the food. When theimage information of the corresponding food is present in the scanneddata of the food, the controller 253 may control the image informationto be displayed as an advertisement image of the corresponding food.

In addition, when a human body detection signal is transmitted, thecontroller 253 may control the supply of drive power to the lightemitting element arrays and the light receiving element arrays of thetouch panel.

FIG. 14 is a view illustrating a display system according to anotherexemplary embodiment of the present invention.

In this exemplary embodiment, the display system includes a plurality ofsystem bodies and a display module mounted in each of the system bodies.

The display modules 200 a to 200 h are divided into a plurality ofgroups A and B. That is, each of the groups includes a plurality ofdisplay modules.

Specifically, group A includes the display modules 200 a to 200 d andgroup B includes the display modules 200 e to 200 h.

The display modules receive commands from a server or a terminal anddisplay images in a multi display performance mode for each group basedon the received commands. Some of the display modules may display imagesin the multi display performance mode and the remainder of the displaymodules may display an image in a single display performance mode.

Images are displayed in the multi display performance mode using thedisplay modules, thereby potentially providing a large-scale display.

The display modules mounted in the showcases may display video whendisplaying images in the multi display performance mode.

Alternatively, all the display modules may display an image in thesingle display performance mode.

The server includes an input unit, a controller, a display unit, astorage unit and a communication unit. The server may include acomputing device.

The input unit allows one of the groups to be selected. Also, the inputunit allows the display module provided in at least one of the showcasesprovided in one of the groups to be selected.

That is, one display module is selected for single display performanceand at least two display modules are selected for multi displayperformance.

The input unit allows a user to select an image to be displayed.

Also, the input unit allows the user to select display conditioninformation for each image, such as display start time, display end timeand display duration.

The input unit may include an input device, such as a keyboard and amouse.

The controller stores data input by the user and/or data transmittedfrom the outside, processes data to be transmitted to at least one ofthe display modules, distributes the processed data, and transmits thedistributed data to the display modules.

The controller may transmit the same data to the display modules so thatthe same image is displayed on all of the display modules.Alternatively, the controller may transmit different data to the displaymodules so that different images are displayed on the display modules.

Also, the controller may transmit the same data to some of the displaymodules and different data to some of the display modules.

Also, the controller may control multi display performance through thedisplay modules.

When a single display command is input to the showcase, the controllertransmits the single display command to the corresponding displaymodule. At this time, the controller transmits image informationselected by a user to the corresponding display module. The imageinformation includes an image to be displayed and display conditioninformation, such as display start time, display end time and displayduration.

When a multi display command of the display modules of the showcases isinput, the controller transmits the multi display command to the displaymodules. Image information includes divided images and display conditioninformation, such as display start time, display end time and displayduration.

More specifically, the controller divides an image selected by a user soas to correspond to the number of the display modules and transmits thedivided images to the showcases considering the sequence of the dividedimages and arrangement order of the display modules.

For example, when the display modules 200 b and 200 c of group A display‘13’ in the multi display performance mode, the left display module 200b displays ‘1’ and the right display module 200 c displays ‘3’.Consequently, ‘13’ are displayed through the display modules 200 b and200 c in the multi display performance mode.

The display unit displays the display modules for each group disposed ata plurality of regions and arrangement information of the displaymodules for each group. The display modules performing display aredistinguished from the display modules not performing display.

Also, the display unit simulates an image to be displayed on theshowcase during single or multi display performance.

The storage unit stores display module information for each region,group information for each display module and various image information.

The communication unit communicates with the showcases through wiredand/or wireless communication. The communication unit transmits variousinformation or a drive command to the showcases in response to a commandfrom the controller.

FIG. 15 is a view illustrating multi display performance. Advertisementimages are displayed through four display modules 200 a, 200 b, 200 cand 200 d included in group A in the multi display performance mode.

At this time, the showcases displaying images in the multi displayperformance mode do not reverse the images when the doors are opened.

In this way, the images are displayed in the multi display performancemode through the display modules having transparent display panelsadjacent to each other, thereby providing a potentially aestheticallypleasing appearance and drawing customer's attention. As a result, anadvertisement effect is improved.

FIG. 16 is a perspective view of a display system according to anotherexemplary embodiment of the present invention.

In the display system according to this exemplary embodiment, ashowcase, as a system body, includes a main body 110, a storage chamber120, shelves 130, a machine compartment 140 and a cool air generatingcompartment 150. Components of the showcase according to this exemplaryembodiment are identical in construction to those of the previousexemplary embodiment excluding the machine compartment and the cool airgenerating compartment, and therefore, a description thereof will beomitted.

The main body 110 forms the external appearance of the showcase. Thestorage chamber 120 is defined in the main body 110. An opening 113 isformed at the front of the main body 110. The machine compartment 140and the cool air generating compartment 150 are disposed at the rear ofthe main body 110. In addition, a cover 146 to cover the machinecompartment is mounted at the rear of the main body 110.

Since the machine compartment 140 and the cool air generatingcompartment 150 are disposed at the rear of the main body 110, the sizeof the opening 113 formed at the front of the main body 110 ismaximized.

A door 200, as a display module, has a size equivalent to the frontopening 113 of the main body 110. The door 200 is hingedly mounted atthe front opening 113 to isolate the storage chamber 120 from theoutside, thereby potentially preventing leakage of cool air from thestorage chamber 120.

The door 200 is wholly formed at the front of the showcase.Alternatively, as in the previous exemplary embodiment, the door may bepartially formed at the front of the showcase. The whole front of theshowcase has a size excluding the external structure constituting themain body.

Also, a transparent display panel may be wholly or partially mounted ina frame 220.

As shown in FIG. 17, the transparent display panel 210 may be partiallymounted in the frame 220. In this case, the transparent display panel210 is mounted in a portion of the frame 220, and a transparent member290, such as transparent glass or transparent plastic, is mounted in theremaining portion of the frame 220. Consequently, the size of thetransparent display panel 210 is reduced, thereby potentially reducingmanufacturing cost of the showcase and providing an advertisement effectthrough the transparent display panel 210.

FIGS. 18 and 19 are perspective views of a display system according toanother exemplary embodiment of the present invention. The displaysystem includes a showcase, as a system body, and a plurality of doors,as display modules.

In the display system according to this exemplary embodiment, theshowcase, as the system body, includes a main body 110, a storagechamber 120, shelves 130, a machine compartment 140 and a cool airgenerating compartment 150. Components of the showcase according to thisexemplary embodiment are identical in construction to those of theprevious exemplary embodiment excluding the storage chamber, the machinecompartment and the cool air generating compartment, and therefore, adescription thereof will be omitted.

The main body 110 forms the external appearance of the showcase. Thestorage chamber 120 is defined in the main body 110. An opening 113 isformed at the front of the main body 110. The machine compartment 140and the cool air generating compartment 150 are disposed at the rear ofthe main body 110.

Rails 114 and 115 are formed at the upper and lower ends of the front ofthe main body 110. A cover to cover the machine compartment 140 ismounted at the rear of the main body 110.

In addition, the main body 110 further includes a control board 116 tocontrol a refrigeration cycle of the showcase. The control board 116 maydetermine a charged state of a second power supply unit in a drivemodule 250 and control the second power supply unit not to be chargedupon determining that the second power supply unit is fully charged.

The main body 110 is provided with a first charging terminal 251 a tosupply power to the second power supply unit in the drive module.

The doors 200, as the display modules, include two doors 200-1 and200-2. The two doors 200-1 and 200-2 are slidably mounted at the mainbody 110 to open and close the storage chamber 120.

The doors 200-1 and 200-2 are mounted on the rails 114 and 115 in thefront opening 113 of the main body 110 so that the doors 200-1 and 200-2are slid from side to side along the rails 114 and 115.

That is, the two doors 200-1 and 200-2 isolate the storage chamber 120from the outside, thereby potentially preventing leakage of cool airfrom the storage chamber 120. Two or more doors may be provided.

The doors 200-1 and 200-2 include transparent display panels 210-1 and210-2 and frames 220-1 and 220-2 to fix the transparent display panels210-1 and 210-2, respectively.

The frames 220-1 and 220-2 constitute edges of the respective doors.

In each of the frames 220-1 and 220-2 is mounted the drive module 250 tosupply drive power to components and control an image to be displayed onthe transparent display panel.

The second power supply unit provided in the drive module 250 may berechargeable. The second power supply unit includes a battery.

The battery has a second charging terminal 251 b contacting the firstcharging terminal 251 a provided in the main body 110 to receive powerfrom a first power supply unit 145 of the main body 110.

That is, when the door is closed, the second power supply unit providedin the drive module 250 comes into contact with the first chargingterminal 251 a provided in the main body 110 to receive power from thefirst power supply unit 145 of the main body 110, converts the receivedpower into drive power to be used by components of the display moduleand supplies the converted power to the respective components of thedisplay module.

When the door is opened, the second power supply unit provided in thedrive module 250 is separated from the first charging terminal 251 a ofthe main body 110 so that the second power supply unit is not charged,converts power stored therein into drive power to be used by therespective components of the display module and supplies the convertedpower to the respective components of the display module.

Power may be supplied from the first power supply unit 145 of the mainbody 110 using a cable provided in the frame 220-1.

A controller in the drive module 250 receives drive power from thesecond power supply unit and controls driving of the transparent displaypanel 210 based on image information stored in the storage unit or imageinformation received through a communication unit.

The controller in the drive module 250 may control multi displayperformance or single display performance through the transparentdisplay panels 210-1 and 210-2.

In addition, the display system further includes door opening andclosing detection units 192 and 193.

Hereinafter, one of the doors, i.e. the door 200-1, will be described indetail as an example.

The main body 110 and the frame 220-1 include the door opening andclosing detection units 192 and 193, respectively. The control board 116of the main body 110 controls driving of the door opening and closingdetection unit 192.

The door opening and closing detection unit may include a temperaturesensor, an infrared sensor, an ultrasonic sensor, a hall sensor or amicro switch.

An example of door opening and closing detection using the infraredsensor will be described.

The infrared sensor includes a light emitting unit 192 provided at themain body 110 and a light receiving unit 193 provided in the door 200-1.The infrared sensor drives the light emitting unit 192 in response to acommand from the control board 116 of the main body, detects lightemitted from the light emitting unit 192 through the light receivingunit 193, and transmits the detected light to the controller 253.

The amount of light detected by the light receiving unit 193 decreasesas the distance between the door 200-1 and the main body 110 isincreased as the result of opening of the door 200-1 and increases asthe distance between the door 200-1 and the main body 110 is decreasedas the result of closing the door 200-1. That is, a door opening anglemay be estimated based on the amount of light. Also, a door open timemay be estimated based on a light amount detection time.

The controller in the drive module 250 confirms a door open degree basedon the amount of light detected by the light receiving unit 193 of theinfrared sensor and determines whether the door opening angle exceeds areference open degree. When the door open degree exceeds the referencedegree, the controller controls an information message indicating thatthe leakage amount of cool air is large, and therefore, the door must beclosed to be displayed on the transparent display panel 210.

Also, the controller in the drive module 250 counts a door open timebased on a light detection time. When the counted door open time exceedsa reference time, the controller 253 controls the image displayed on thetransparent display panel 210 to be changed. The changed image requeststhat the door be closed.

An example of door opening and closing detection using the hall sensorwill be described.

Protrusions of different lengths are formed at the main body 110, andthe hall sensor is mounted in the door so that the hall sensor facesdifferent protrusions as the door is slid. That is, the hall sensordetects the intensity of a magnetic field of the protrusions which thehall sensor faces during sliding of the door, converts the detectedintensity of the magnetic field into voltage, and transmits theconverted voltage to the controller 253.

At this time, the controller in the drive module 250 confirms opening ofthe door based on the voltage detected by the hall sensor and counts adoor open time. When the counted door open time exceeds a referencetime, the controller controls the image displayed on the transparentdisplay panel 210 to be changed. The changed image requests that thedoor be closed.

Alternatively, the controller in the drive module 250 may estimate adoor open degree based on the voltage detected by the hall sensor,estimate the leakage amount of cool air corresponding to the door opendegree and display how freshness of food in the storage chamber isaffected by the estimated leakage amount of cool air. Also, thecontroller in the drive module 250 may display power consumption due toleakage of cool air.

An example of door opening and closing detection using the micro switch(not shown) will now be described.

When the door is closed, the micro switch is turned on. When the door isopened, the micro switch is turned off.

That is, an off signal is transmitted from the micro switch, thecontroller in the drive module 250 determines that the door is openedand counts an off time of the micro switch to estimate a door open time.

The controller in the drive module 250 compares the door open time witha reference time. When the door open time exceeds the reference time,the controller 253 controls an image requesting that the door be closedto be output.

FIGS. 20 to 34 are views illustrating display modules according to otherexemplary embodiments of the present invention.

The display modules are installed in indoor and outdoor structures toprovide aesthetically pleasing indoor and outdoor environments and toprovide various information to people. The display modules may include atelevision, a bus shelter, an information drive module, a show window, awindow, a mural and a floor mat.

FIG. 20 is a front perspective view of a television, as a displaymodule, according to another exemplary embodiment of the presentinvention, FIG. 21 is a rear perspective view of the televisionaccording to the exemplary embodiment of the present invention, and FIG.22 is a control block diagram of the television according to theexemplary embodiment of the present invention.

A television 300 is installed in a house or a public place by a mountholder to receive an analog broadcasting signal transmitted frombroadcasting stations, to convert the received broadcasting signal intoa digital signal, thereby allowing the reproducing of an image andsound. The mount holder may be of a wall type, a ceiling type or a tabletype.

The television may perform two-way communication.

The television 300 requests content from a content server (not shown)through the Internet, receives requested content from the content serverand reproduces the received content, thereby potentially providingvarious Internet services.

That is, the television provides various content and supplementaryservices, such as audio on demand (AOD), video on demand (VOD),multicast, local music file playback, Internet browsing using a remotecontrol, home shopping, home banking and online games, through theInternet. In addition, the television provides a broadcast desired by auser at time desired by the user unlike general over-the-airbroadcasting, cable broadcasting or satellite broadcasting.

Also, the television allows image communication to be performed throughthe Internet and may be used as a picture frame or a schedule displaydevice when the television is not watched or the Internet is not used.

As shown in FIGS. 20 and 21, the television 300, as the display module,includes a transparent display panel 310, a frame 320, a blocking member330, a support member 340 and a fixing member 350. In this exemplaryembodiment, a television installed in the table type mount holder willbe described as an example.

The transparent display panel 310 displays at least one image selectedfrom a group consisting of a broadcast image, a content image, acommunication image and a picture in response to a command from acontroller provided in a drive module 360.

The transparent display panel 310 may be an LCD or an OLED. Hereinafter,the LCD, as the transparent display panel, will be described.

The transparent display panel 310 includes a light source, a firstpolarizing plate, a light guide plate, a liquid crystal panel and asecond polarizing plate. The light source, the first polarizing plate,the light guide plate, the liquid crystal panel and the secondpolarizing plate constituting the transparent display panel 310 areidentical in arrangement, transparency control and image display tothose shown in FIG. 4, and therefore, a description thereof will beomitted.

The transparent display panel may be a transparent touch display panel.

The transparent touch display panel includes a light source, a firstpolarizing plate, a light guide plate, a liquid crystal panel, a secondpolarizing plate, a touch panel, light emitting element arrays and lightreceiving element arrays. The light source, the first polarizing plate,the light guide plate, the liquid crystal panel, the second polarizingplate, the touch panel, the light emitting element arrays and the lightreceiving element arrays constituting the transparent touch displaypanel are identical in arrangement, transparency control and imagedisplay to those shown in FIG. 12, and therefore, a description thereofwill be omitted.

In addition, a first sheet and a second sheet may be disposed atopposite sides of the transparent touch display panel 310.

The first sheet is a heat insulation sheet provided at the rear of thetransparent touch display panel 310. The second sheet is ananti-reflective coating film provided at the front of the transparenttouch display panel 310 to prevent light reflection.

The frame 320 fixedly supports one side of the transparent touch displaypanel 310. That is, the transparent touch display panel 310 is fitted inthe frame 320. Consequently, the thickness D3 of the transparent displaypanel 310 of the display module is less than the thickness D4 of theframe 320.

The surface area A3 of the transparent display panel 310 is greater thanthe surface area A4 of the frame 220.

In the frame 320 are provided a power button 321 to turn power on andoff, a signal detection unit 322 to receive a signal from a remotecontrol, a camera 323 and a microphone 324 for image communication, atransparency adjustment button 325 to adjust transparency of thetransparent display panel and a speaker 326 to output sound.

In the frame 320 is further provided a drive module 360 to controldriving of the transparent display panel 310.

The blocking member 330 is provided at the edge of the transparentdisplay panel 310 to fix the first polarizing plate, the light guideplate, the liquid crystal panel and the second polarizing plateconstituting the transparent display panel 310 and to prevent light inthe transparent display panel 310 from scattering to the outside.

The bottom of the support member 340 contacts a table and the side ofthe support member 340 contacts the rear of the frame 320 to support amain body. The support member 340 may be integrally formed at the frame320.

As shown in FIG. 21, the support member 340 supports the frame 320 andthe transparent display panel 310 at a predetermined angle.

The predetermined angle is an angle at which an image on the transparentdisplay panel has the maximum image quality when a user views the image.In addition, the support member 340 may include an angle adjustment unitto adjust the angle at which the frame 320 and the transparent displaypanel 310 are supported.

The support member 340 has a terminal unit 341. The terminal unit 341includes various components and digital terminals. The terminals areconcentrated on a predetermined region to provide an aestheticallypleasing appearance and to achieve easy connection with various devices.

The fixing member 350 is provided at the rear of the main body 110 tofix the support member 340.

FIG. 22 is a control block diagram of the television. The televisionincludes a second power supply unit 361, a signal detection unit 362, aninput unit 363, a controller 364, a storage unit 365, a display driveunit 366, a sound drive unit 367 and a communication unit 368. Thesecomponents may be provided in the drive module 360.

The second power supply unit 361 is connected to a first power supplyunit, such as an adaptor, provided at a cable connected to a set top boxor a commercial power source to receive power from the first powersupply unit, to covert the received power into drive power to be used bycomponents and to supply the converted power to the respectivecomponents.

In addition, the second power supply unit 361 may be connected to thecommercial power source to receive power from the commercial powersource, to covert the received power into drive power to be used bycomponents and to supply the converted power to the respectivecomponents.

The signal detection unit 362 detects a signal transmitted from theremote control and transmits the detected signal to the controller 3364.The signal transmitted from the remote control may include a broadcastchannel signal, a volume control signal, a mode selection signal, aletter signal for Internet connection, image communication and scheduleinput, a picture frame design selection signal (if the television isused as a picture frame) and a content selection signal.

The input unit 363 includes an image input unit and/or a sound inputunit.

When an image signal captured by a camera is received, the image inputunit processes the received image signal and transmits the processedimage signal to the controller 364. The sound input unit transmits asound signal collected by a microphone to the controller 364.

When a power off signal is input by the power button 331, the controller364 controls driving of the display drive unit to be stopped so that thetransparent display panel is transparent.

When a transparency selection signal is input by the transparencyadjustment button 325, the controller 364 controls driving of thedisplay drive unit to be stopped so that the transparency of thetransparent display panel is adjusted.

The controller 364 controls driving of at least one selected from agroup the camera 323, the microphone 324, the speaker 326 and thetransparent display panel 310 in response to a mode selection signaltransmitted from the signal detection unit 362.

The mode may include a broadcast mode, an Internet mode, an imagecommunication mode, a picture frame mode, a schedule mode and a calendarmode, which will be described in more detail.

When a broadcast mode selection mode is transmitted from the signaldetection unit 362, the controller 364 controls the communication unit368 to receive a broadcast signal. Also, the controller 364 controls thedisplay drive unit 366 and the sound drive unit 367 to output an imagethrough the transparent display panel and sound through the speaker.

When an Internet mode selection signal is transmitted from the signaldetection unit 362, the controller 364 controls the communication unit368 to be connected to the Internet. When the communication unit 368 isconnected to the Internet, the controller 364 controls the display driveunit 366 to display an Internet image on the transparent display panel310. Based on a letter signal transmitted from the signal detection unit362, the controller 364 controls the communication unit to be connectedto a site corresponding to the letter.

The controller 364 controls the display drive unit 366 to display animage corresponding to the connected site on the transparent displaypanel. Also, the controller 364 controls the sound drive unit 367 tooutput sound through the speaker.

When an image communication mode selection signal is transmitted fromthe signal detection unit 362, the controller 364 controls driving ofthe communication unit 369 so that the communication unit is connectedto the Internet. Based on a signal transmitted from the signal detectionunit 362, the controller 364 controls communication connection with aterminal owned by a person who wishes to perform image communication.Also, the controller 364 controls the camera and the microphones toacquire user image and sound.

When user image and sound signal are input from the camera 323 and themicrophone 324 in the image communication mode, the controller 364controls the communication unit 368 to transmit the user image and soundsignals to the terminal of the other party through the Internet so thatthe user image and sound signals are output to the terminal of the otherparty. When other party image and sound are transmitted, the controller364 controls the display control unit 366 to display the other partyimage on the transparent display panel and the sound drive unit 367 tooutput the other party sound through the speaker.

At this time, the controller 364 may control the display drive unit 366to display the other party image on the transparent display panel 310.

That is, during image communication, both the user image and the otherparty image may be displayed on the transparent display panel 310.

When a picture frame mode selection signal is transmitted from thesignal detection unit 362, the controller 364 controls a display mode ofthe transparent display panel 310 to be changed into a picture framemode. When a picture frame design selection signal and a pictureselection signal are transmitted from the signal detection unit 362, thecontroller 364 controls a picture frame design and a picture to bedisplayed so that the television is utilized as interior decoration.

In addition, picture frame designs may be displayed in order stored inthe storage unit 365 in response to a direction key signal of the remotecontrol and one of the picture frame designs may be selected in responseto a confirmation key signal of the remote control. Alternatively, allpicture frame designs stored in the storage unit 365 may be displayedand one of the picture frame designs may be selected in response to adirection key signal of the remote control. The picture is selected inthe same manner as the picture frame design.

When a schedule mode selection signal is transmitted from the signaldetection unit 362, the controller 364 controls a display mode of thetransparent display panel 310 to be changed into a schedule mode andcontrols the display drive unit 366 to display a schedule stored in thestorage unit 365 on the transparent display panel 310.

When schedule information is input from the signal detection unit 362 inthe schedule mode, the controller 364 controls the storage unit 365 tostore the input schedule information into the storage unit 365.

The controller 365 controls the sound drive unit 367 to output theschedule information as sound. At this time, sound may be output apredetermined time before the scheduled time.

When a calendar mode selection signal is transmitted from the signaldetection unit 362, the controller 364 controls a calendar showing thismonth to be output.

At this time, calendar designs may also be selected. Also, a calendarshowing twelve months or this month and the next month may be displayedaccording to user selection.

The storage unit 365 stores calendar information, calendar designinformation, picture frame design information, picture information,telephone number information and schedule information.

The display drive unit 366 drives the liquid crystal cells of thetransparent display panel 310 to display an image on the transparentdisplay panel 310 in response to a command from the controller 364.

The display drive unit 366 drives the liquid crystal cells of thetransparent display panel 310 to adjust the transparency of thetransparent display panel 310 in response to a command from thecontroller 364.

The sound drive unit 367 outputs sound through the speaker according toa command from the controller 364.

In the broadcast mode, the communication unit 368 is connected to anover-the-air broadcasting station or a cable broadcasting station toreceive a broadcast signal. In the Internet mode, the communication unit368 is connected to the Internet to communicate with the Internetthrough two-way communication.

The communication unit 368 may communicate with the user terminal toreceive images, such as pictures, from the user terminal.

As shown in FIG. 23, the communication unit 368 includes a broadcastsignal receiving unit 368 a to receive broadcast data, a wirelesscommunication unit 368 b to transmit and receive data through wirelesscommunication and a wired communication unit 368 c to transmit andreceive data through wired communication. The respective communicationunits 368 a, 368 b and 368 c transmit data to a first signal processingunit 364 a of the controller 364.

The controller 364 includes a first signal processing unit 364 a, asecond signal processing unit 364 b and a display controller 364 c.

The first signal processing unit 364 a process data transmitted from thecommunication unit 364, the second signal processing unit 364 b processdata transmitted from the storage unit 365, and the display controller364 c creates a drive command corresponding to the processed data andoutputs the created drive command to the display drive unit.

The first signal processing unit 364 a may includes a signal processingunit to process broadcast data, a signal processing unit to processwireless data and a signal processing unit to process wired data.

If a transparent touch display panel is provided in the television 300,the drive module 360 includes a touch drive unit 369. The touch driveunit 369 includes a light drive part and a position detection part.

The transparent touch display panel is a combination of a touch panel toallow a user to input a command and a display panel to provide an imageto the user. The touch panel is included as the input unit in additionto the remote control.

In the same manner as the remote control, position signals, such as aplurality of mode buttons, a key display button, character keys andspecial character keys, are input to the touch panel.

The touch drive unit 369 drives the light emitting element arrays andthe light receiving element arrays to acquire the point of a touch pointon the touch panel.

The light drive part drives the light emitting element arrays to emitlight in response to a command from the controller 364.

The position detection part recognizes light receiving elements havingtransmitted a light detection signal as 1 and a light receiving elementhaving transmitted a light non-detection signal as 0. The positiondetection part confirms the position of the light receiving elementrecognized as 0, detects the position of a touch point and transmits theposition of the detected touch point to the controller 364.

The controller 364 controls driving of the display drive unit 366 basedon the position of a touch point detected by the position detectionpart.

More specifically, when position information of the touch point istransmitted, the controller 364 confirms the currently displayed imageinformation, confirms a key present at the position of the touch pointamong keys included in the confirmed image, and controls an imagecorresponding to the confirmed key to be displayed or performs afunction corresponding to the confirmed key.

For example, when the position of the touch point coincides with theposition of the broadcast mode button in a state in which the broadcastmode button, the Internet mode button, the image communication button,the picture frame mode button, the schedule mode button, the calendarmode button are displayed on the transparent touch display panel 310,the controller 364 controls the broadcast mode.

When an arbitrary region is touched irrespective of a mode to beperformed, the controller 364 controls the mode buttons to be displayed.

When the key display button is touched by a user, the controller 364confirms the current mode. When the current mode is the broadcast modeor the calendar mode, the controller 364 controls numeric keys anddirection keys to be displayed. When the current mode is the Internetmode, the image communication mode or the schedule mode, the controller364 controls English alphabet keys, Korean alphabet keys, numeric keysand special character keys to be displayed.

The storage unit 365 stores position information regarding the modebuttons, position information regarding the key display button, positioninformation regarding the character keys for each mode, positioninformation regarding the special character keys for each mode andposition information regarding the direction keys for each mode.

Also, the storage unit 365 stores positions of the light receivingelements of the light receiving element arrays.

FIG. 24 is a view illustrating a bus shelter, as a display module,according to another exemplary embodiment of the present invention.

The bus shelter is provided at a bus stop to provide a place where bususers may shelter themselves from rain or snow.

The bus shelter provides information regarding buses stopped at the busstop, an advertisement image and map information related to thesurroundings of the bus shelter.

The bus shelter 400 includes a plurality of supports 410, 420 and 430, acover member 440 and a plurality of display modules 450, 460 and 470.

The display modules include transparent display panels 451, 461 and 471and frames 452, 462 and 472 to fix the respective transparent displaypanels 451, 461 and 471.

The first support 410 fixedly supports the first display module 450 andthe second display module 460. The second support 420 fixedly supportsthe first display module 450 and the third display module 470. The thirdsupport 430 fixes the first support 410 and the second support 420 andfixedly supports the cover member 440.

The cover member 440 is fixed to the third support 430 to prevent thedisplay modules 450, 460 and 470 from being exposed to rain and snow.

Each of the display modules 450, 460 and 470 includes a drive module tocontrol driving of the transparent display panel.

A frame may be provided at only one side of each of the first, secondand third display modules 450, 460 and 470, and blocking members 451,461 and 471 may be provided at the other sides of the display modules450, 460 and 470.

Each of the blocking members fixes a first polarizing plate, a lightguide plate, a liquid crystal panel and a second polarizing plateconstituting the transparent display panel 310 and prevents light in thetransparent display panel 310 from scattering to the outside.

The transparent display panels of the first, second and third displaymodules 450, 460 and 470 may be transparent touch display panels.Alternatively, only the transparent display panel of one of the first,second and third display modules 450, 460 and 470 may be a transparenttouch display panel.

FIG. 25 is a control block diagram to control driving the displaymodules provided in the bus shelter according to the exemplaryembodiment of the present invention, which will be described withreference to FIGS. 26 and 27.

A drive module 480 includes a power supply unit 481, a touch drive unit482, a controller 483, a storage unit 484, a display drive unit 485, asound drive unit 486 and a communication unit 487. Hereinafter, a casein which only the first transparent display panel is a transparent touchdisplay panel will be described as an example.

The power supply unit 481 receives power from an adaptor provided at acable connected to a commercial power source, coverts the received powerinto drive power to be used by components and supplies the convertedpower to the respective components.

In addition, the power supply unit 481 may be connected to thecommercial power source to receive power from the commercial powersource, to covert the received power into drive power to be used bycomponents and to supply the converted power to the respectivecomponents.

A light drive part of the touch drive unit 482 drives light emittingelement arrays provided in the touch panel of the first transparenttouch display panel to emit light.

The position detection part of the touch drive unit 482 recognizes lightreceiving elements having transmitted a light detection signal as 1 anda light receiving element having transmitted a light non-detectionsignal as 0. The position detection part confirms the position of thelight receiving element recognized as 0, detects the position of a touchpoint and transmits the position of the detected touch point to thecontroller 483.

The controller 483 controls driving of the display drive unit 485 basedon the position of a touch point detected by the position detectionpart.

More specifically, when position information of the touch point istransmitted, the controller 483 confirms the currently displayed imageinformation, confirms a button present at the position of the touchpoint among buttons included in the confirmed image, and controls animage corresponding to the confirmed button to be displayed or performsa function corresponding to the confirmed button.

The buttons include an advertisement mode button B1, a bus mode buttonB2 and a nature mode button B3. The buttons B1, B2 and B3 are present inan image displayed on the first transparent display panel 450.

The buttons are selected by bus users. The buttons are displayed on onlythe first transparent display panel including the touch panel.

More specifically, when the position of the touch point coincides withthe position of the advertisement mode button B1, the controller 483controls first, second and third display drive units 485 a, 485 b and485 c to display an advertisement image on the first, second and thirdtransparent display panels 451, 461 and 471.

At this time, the images may be displayed on the first, second and thirdtransparent display panels 451, 461 and 471 in the multi displayperformance mode. Also, the images may be displayed as video when theimages are displayed in the multi display performance mode.

Also, the image may be displayed on the first, second and thirdtransparent display panels 451, 461 and 471 in a single displayperformance mode. At this time, a primary advertisement image isdisplayed on the first transparent display panel 451 and secondaryadvertisement images is displayed on the second and third transparentdisplay panels 461 and 471.

In the advertisement mode, the controller 483 controls an additionalinformation button to be displayed. When the additional informationbutton is touched by a user, the controller 483 controls a store whichsells the advertising object, a route map of the store, priceinformation of the advertising object, event information and a discountcoupon image to be displayed.

FIG. 26 is a view illustrating application of the bus shelter. When adiscount coupon image 463 of an advertising object is displayed on thesecond transparent display panel 462, a bus user may acquire and storethe discount coupon image using his/her terminal and may show the couponstored in the terminal to a salesperson to get a discount with respectto a corresponding article.

At this time, the bus user may visit the store based on the route map ofthe store displayed on the third transparent display panel 471.

When the position of the touch point coincides with the position of thebus mode button B2, the controller 483 controls the first, second andthird display drive units 485 a, 485 b and 485 c to display businformation on the first, second and third transparent display panels451, 461 and 471.

The bus information includes bus numbers stopped at this bus stop, routeinformation for each bus number, information regarding arriving busesand bus waiting time information.

In the bus mode, the controller 483 controls the character keys and thenumeric keys to be displayed, confirms a character corresponding to theposition of the touch point touched by the user and controls the businformation to be displayed based on the confirmed character.

For example, bus numbers stopped at destination input in a destinationcolumn may be displayed, and the route of a bus corresponding to thenumber input in the bus number column may be displayed. At this time, amap showing the surroundings of the bus stop may be also displayed.

As shown in FIG. 27, a small amount of information is displayed in thebus mode. Consequently, the controller 483 may control at least onetransparent display panel of the second and third display modules 460and 470 not to be driven. The transparent display panel, which is notdriven, remains transparent.

When the position of the touch point coincides with the position of thenature mode button B3, the controller 483 controls the first, second andthird display drive units 485 a, 485 b and 485 c to display an image ofnature on the first, second and third transparent display panels 451,461 and 471.

At this time, the image of nature displayed on the first, second andthird transparent display panels 451, 461 and 471 may be displayed in amulti display performance mode. The image may be displayed as video inthe multi display performance mode.

The image of nature includes an image of the sea, an image of forest, animage of four seasons, an image of cultural assets and an image ofspecialty products and sightseeing places in an area in which acorresponding bus stop is located.

In the nature mode, the controller 483 controls driving of the firstdisplay drive unit 485 a to display an image selection button so that abus user may select a desired image.

The storage unit 484 stores advertisement image information, informationregarding stores that sell the advertising object, route mapinformation, discount coupon information, bus number information, routeinformation for each bus number, an image of cultural assets and animage of specialty products and sightseeing places in an area in which acorresponding bus stop is located.

The storage unit 484 further stores sound information to explaincultural assets, sound information to explain sightseeing places andsound information to explain specialty products.

The display drive unit 485 includes the first display drive unit 485 ato drive the first transparent display panel 451, the second displaydrive unit 485 b to drive the second transparent display panel 461 andthe third display drive unit 485 c to drive the third transparentdisplay panel 471. The respective first display drive unit 485 a, 485 band 485 c display images on the respective transparent display panel inresponse to commands from the controller 483.

In the bus mode, the sound drive unit 486 outputs the number of anarriving bus as sound in response to a command from the controller 483.In the advertisement mode, the sound drive unit 486 outputsadvertisement sound. In the nature mode, the sound drive unit 486outputs sound to explain a displayed image.

The communication unit 487 communicates with a bus arrival notifyingserver (not shown) to receive information regarding arriving buses andwaiting time information for each bus.

The communication unit 487 communicates with the terminal through wiredand/or wireless communication to receive update information to updateimage information and bus information stored in the storage unit 484.

FIGS. 28A and 28B are perspective views of an information board, as adisplay module, according to another exemplary embodiment of the presentinvention. FIG. 29 is a view illustrating application of the informationboard.

The information board 500 is installed in a sightseeing place, a museum,a large-scale supermarket or a hotel to display the position of arestroom, suggestions, the position of an elevator, an information mapand a greeting message.

The information board 500 includes supports 510 and 520, support rests530 and first, second and third display modules 540, 550 and 560.

The supports 510 and 520 are formed in the shape of a rod. The displaymodules 540, 550 and 560 are fitted on the supports 510 and 520. At thistime, the first parent display module is fixedly mounted to the supports510 and 520. Also, a cable to transmit a drive signal to the second andthird transparent display modules 550 and 560 is disposed in thesupports 510 and 520.

In addition, each of the supports 510 and 520 may include a fixing unit(not shown) to adjust heights of transparent display panels and fix thetransparent display panels at the adjusted heights.

The support rests 530 are provided at the upper and lower ends of therespective supports 510 and 520 to safely fix the supports 510 and 520to the floor and the ceiling.

The first, second and third display modules 540, 550 and 560 aredisposed in a stacked structure.

A first frame 542 is provided at the lower end of a first transparentdisplay panel 541 of the lowermost one of the first, second and thirddisplay modules, i.e. the first display module 540. A blocking member545 is provided at the upper end of the first transparent display panel541. Blocking members 554, 555, 564 and 565 are provided at the upperand lower ends of second and third transparent display panels 551 and561.

The blocking members 554, 555, 564 and 565 fix a first polarizing plate,a light guide plate, a liquid crystal panel and a second polarizingplate constituting each transparent display panel and to prevent lightin the transparent display panel from scattering to the outside.

Each of the first, second and third display modules 540, 550 and 560includes a drive module to control driving of a correspondingtransparent display panel. The respective drive modules performcommunications.

Alternatively, a drive module 570 to control driving of the first,second and third display modules 540, 550 and 560 may be disposed in thefirst frame 542. At this time, the drive module 570 in the first frame542 may transmit drive signals to the second and third display modules550 and 560 via cables disposed in the first and second supports 510 and520.

The first transparent display module 541 is fitted in the first frame542. The first, second and third transparent display panels 541, 551 and561 are fitted in side frames 543, 544, 552, 553, 562 and 563.

That is, the lower end of the first transparent display module 541 isfixed by the first frame 542. Opposite sides of the first, second andthird transparent display panels 541, 551 and 561 are fixed by the sideframes 543, 544, 552, 553, 562 and 563.

Consequently, the thickness of the first, second and third transparentdisplay panels 541, 551 and 561 of the display modules is less than thethickness D4 of the respective frames 542, 543, 544, 552, 553, 562 and563.

The surface area of the first transparent display panel 541 is greaterthan that of the frames 542, 543 and 544. The surface area of the secondtransparent display panel 551 is greater than that of the frames 552 and553. The surface area of the third transparent display panel 561 isgreater than that of the frames 562 and 563.

The first frame 542 and the side frames 543 and 544 may be integrallymanufactured.

The first, second and third transparent display panels 541, 551 and 561displays images in a multi display performance mode in response to acommand from the controller in the drive module 570.

In the side frames 543, 544, 552, 553, 562 and 563 are formed holes,through which the supports 510 and 520 extend. Consequently, the first,second and third display modules 540, 550 and 560 may move along thesupports 510 and 520.

As shown in FIG. 28B, the first, second and third display modules 540,550 and 560 may be separated from each other. In a separated state, thefirst, second and third display modules 540, 550 and 560 display imagesin a single display performance mode.

As shown in FIG. 29, the first, second and third transparent displaypanels 541, 551 and 561 of the first, second and third display modules540, 550 and 560 display at least one selected from a group consistingof the position of a restroom, suggestions, the position of an elevator,an information map, a greeting message, open time and close time.

For example, one of the first, second and third transparent displaypanels 541, 551 and 561 may display close time a predetermined timebefore the close time in response to a command from the drive module570.

The drive module 570 of the information board 500 communicates with aterminal through wired and/or wireless communication to update images tobe displayed on the first, second and third transparent display panels.

The information board may display only necessary information as an imageso that people or things behind the information board may be viewedthrough the information board. In a sightseeing place, the informationdrive module may be prevented from destroying the scenic beauty.

FIG. 30 is a control block diagram of the display module according tothe exemplary embodiment of the present invention. Control configurationof one of the display modules, i.e. the first display module 540, willbe described as an example.

The drive module 570 to control the first display module 540 includes asecond power supply unit 571, a communication unit 572, a controller 573and a display drive unit 574.

The second power supply unit 571, the communication unit 572, thecontroller 573 and the display drive unit 574 are provided in the drivemodule 570 disposed in the frame 542 of the first display module 540.

The second power supply unit 571 receives power from an external firstpower supply unit, converts the received power into drive power of thecommunication unit, drive power of the controller and drive power of thedisplay drive unit, and supplies the converted power to thecommunication unit 572, the controller 573 and the display drive unit574.

The communication unit 572 receives data from a server or a terminal andtransmits the received data to the controller 573. The communicationunit 572 performs wired and/or wireless communication.

In addition, the server communicates with the communication unit 572through wired and/or wireless communication. The terminal communicateswith the communication unit 572 through wireless communication, such asWiFi or Bluetooth.

Also, the terminal may be an administrator terminal which directlycontrols driving of the transparent display panel 540.

The communication unit 572 may communicate with the second and thirddisplay modules through wireless communication to display images in amulti display performance mode.

The controller 573 processes the received data and outputs a drivecommand corresponding to the processed data to the display drive unit574. At this time, the controller 573 receives data in a predeterminedformat and decodes the received data.

The display drive unit 574 drives the transparent display panel inresponse to a command from the controller so that data are displayed onthe transparent display panel.

The display drive unit 574 drives liquid crystal cells of the liquidcrystal panel in response to the command from the controller 573 so thatan image is displayed on the transparent display panel 541 and thetransparency of the transparent display panel is adjusted.

The display module may further include a storage unit to store data andan input unit to allow data received by the communication unit or storedin the storage unit to be selected.

At this time, the controller confirms the data selected through theinput unit, processes the confirmed data, and transmits a drive commandcorresponding to the processed data to the display drive unit 574.

In a case in which a plurality of data is stored in the storage unit,the controller 573 may control one of the data to be displayed or thedata to be sequentially displayed at a predetermined interval.

The data stored in the storage unit are transmitted from the serverand/or the terminal. The data may be stored in a compressed file format.

The drive module 570 includes a reading unit to read a tag owned by auser. The drive module 570 confirms name and ID of a customer based ondata of the tag read by the reading unit and controls the display driveunit 574 to display information regarding the customer.

More specifically, the drive module 570 confirms the name and ID of thecustomer in the tag and controls an image, such as a welcome message ora farewell message, as well as the name or nickname of the customer tobe displayed on the transparent display panel,

For example, when the information board 500 is installed at the entranceof a shopping center, such as a department store or a large-scalesupermarket, a tag of a person entering the shopping center is read anda message ‘Welcome’ together with the name of the person entering theshopping center is displayed on the information drive module. Also, atag of a person exiting the shopping center is read and a message ‘Goodbye’ together with the name of the person exiting the shopping center isdisplayed on the information drive module. At this time, the drivemodule may consider a customer having paid the bills as a person exitingthe shopping center through communication with an administratorterminal.

FIG. 31 is a view illustrating a show window, as a display module,according to another exemplary embodiment of the present invention.

The show window 600 is installed at a restaurant, a fast-foodrestaurant, a clothing store, a department store, a café to display newmerchandise or popular merchandise and thus to draw person's attentionso that customers are guided into the store.

The show window 600 is installed at a wall or a glass window. The showwindow 600 includes a plurality of display modules 610, 620 and 630.

The first display module 610 includes a first transparent display panel611, a first frame 612 and a blocking member 613. The second displaymodule 620 includes a second transparent display panel 621, a secondframe 622 and blocking members 623 and 624. The third display module 630includes a third transparent display panel 631, a third frame 632 and ablocking member 633.

Each of the display modules 610, 620 and 630 includes a drive module tocontrol driving a corresponding transparent display panel. The drivemodules are disposed in the respective frames.

Alternatively, a drive module may be disposed in a frame to controldriving the display modules.

The first, second and third frames 612, 622 and 632 fix the transparentdisplay panels 611, 621 and 631, respectively.

The first, second and third transparent display panels 611, 621 and 631of the transparent display panels form a row. That is, the first, secondand third transparent display panels 611, 621 and 631 are disposedadjacent to each other in the horizontal direction.

Consequently, the first, second and third transparent display panels611, 621 and 631 are fixed by a single frame, and the blocking members613, 623 and 633 are provided at interfaces between the first, secondand third transparent display panels.

Each of the blocking members 613, 623 and 633 fixes a first polarizingplate, a light guide plate, a liquid crystal panel and a secondpolarizing plate constituting the transparent display panel and preventslight in the transparent display panel from scattering to the outside.

The first, second and third display modules 610, 620 and 630 displaymerchandise, popular merchandise and new merchandise sold at acorresponding store, price information and size information.

If the store is a fast-food restaurant, as shown in FIG. 31, an imageand price of a new menu, i.e. a hamburger, sold at the fast-foodrestraint are displayed on the first transparent display panel, an imageand price of another new menu, i.e. a beverage, are displayed on thethird transparent display panel, and open time is displayed on thesecond transparent display panel.

The first, second and third transparent display panels 611, 621 and 631display images in a multi display performance mode in response to acommand from the drive module 650.

In addition, the first, second and third transparent display panels 611,621 and 631 may display a image in a single display performance mode.Also, some of the first, second and third transparent display panels611, 621 and 631 may be driven, and the remainder of the first, secondand third transparent display panels 611, 621 and 631 may not be driven.

When the first, second and third transparent display panels 611, 621 and631 are not be driven, the first, second and third transparent displaypanels 611, 621 and 631 remain transparent so that people may see theinterior of the restaurant through the transparent display panels.

The drive module 640 of the show window 600 communicates with a terminalthrough wired and/or wireless communication to update images to bedisplayed on the first, second and third transparent display panels.

In this way, the show window is configured using the transparent displaypanels, thereby potentially increasing an advertisement effect,improving the image of a company, reducing printing cost of advertisingbills and lowering troubles in attaching and detaching the advertisingbills.

FIG. 32 is a view illustrating a window according to another exemplaryembodiment of the present invention.

The window 700 is formed at a wall to receive air or sunlight and toenable a person to look out therethrough. The window 700 is configuredusing a transparent display panel.

A display module mounted at the window 700 includes a frame 710 and atransparent display panel 720.

The frame 710 fixes the transparent display panel 720. In the frame 710is provided a drive module to control driving of the transparent displaypanel 720.

The frame 710 fixes a first polarizing plate, a light guide plate, aliquid crystal panel and a second polarizing plate constituting thetransparent display panel and prevents light in the transparent displaypanel from scattering to the outside.

The transparent display panel 720 displays a blind image, a beautifulpainting image or a nature image in response to a command from the drivemodule 730.

The image displayed on the transparent display panel 720 of the windowmay be changed using a terminal.

In addition, the frame of the window further includes a mode changebutton, which may be manipulated to change an image displayed on thetransparent display panel 720.

When not driven, the transparent display panel 720 remains transparentso that a user may look out of the window.

The drive module 730 of the window 700 communicates with a terminalthrough wired and/or wireless communication to update an image to bedisplayed on the transparent display panel 720.

In this way, the window is configured using the transparent displaypanel, thereby potentially maximizing an interior effect in a house.

FIG. 33 is a view illustrating a floor mat, as a display module,according to yet another exemplary embodiment of the present invention.FIG. 34 is a view illustrating the structure of the floor mat.

The floor mat 800 is installed in a public place, such as a park or anamusement park, or a house. The floor mat 800 is configured using atransparent display panel.

The floor mat 800 includes a frame 810 and a transparent display panel820.

The frame 810 fixes the transparent display panel 820. In the frame 810is provided a drive module 830 to control driving of the transparentdisplay panel 820.

The frame 810 fixes a first polarizing plate, a light guide plate, aliquid crystal panel and a second polarizing plate constituting thetransparent display panel 820 and prevents light in the transparentdisplay panel from scattering to the outside.

The transparent display panel 820 displays a trick art image, a floormaterial image or a nature image in response to a command from the drivemodule 830.

The trick art image includes a plurality of realistic images havingvarious concepts. The floor material image includes an floor image of aspace where the floor mat is installed. The nature image includes anaquarium image and a garden image. The floor material image is capturedand transmitted by a terminal.

The image displayed on the transparent display panel 820 of the floormat 800 may be changed using the terminal.

The drive module 830 of the floor mat 800 communicates with the terminalthrough wired and/or wireless communication to update an image to bedisplayed on the transparent display panel 820.

Since the transparent display panel 820 is installed at the floor wherepeople walk as shown in FIG. 33, the transparent display panel 820 maybe broken. For this reason, the transparent display panel 820 is coveredby a reinforced member 840, such as tempered glass, as shown in FIG. 34.

In this way, the floor mat is configured using the transparent displaypanel, thereby potentially maximizing an interior effect in a house andcreating a special procurement boom in tourism.

As is apparent from the above description, an image is displayed using atransparent display module, thereby potentially improving spatialefficiency and providing an aesthetically pleasing space.

Also, image information received from the outside through wired and/orwireless communication or data stored in a storage unit is selectivelydisplayed on a transparent display module, thereby providing for thepotential easy management of the displayed image.

A transparent display module is installed in a showcase, as a displaysystem, and an image is displayed, thereby providing for the potentialsimultaneously viewing of articles in the showcase and an image.

Also, an advertisement image is displayed on a transparent displaypanel, thereby potentially reducing manufacturing and managing cost ofadvertising bills, and the advertisement image is variously displayed,thereby potentially maximizing an advertisement effect and improving theimage of a company.

Also, if the display system is a showcase, article information isdisplayed on a transparent display module, thereby potentiallyeliminating trouble in drawing articles from the showcase to confirmarticle information and reducing door opening and closing frequency.

In addition, if the display system is a refrigerating showcase, leakageof cool air due to opening of a door is prevented, thereby potentiallyimproving a cooling effect and reducing power consumption due to arefrigeration cycle operation.

Also, if the display system is a showcase, an image displayed on a door,as a display module, is reversed according to a door opening angle, andtherefore, an image displayed on the door is correctly viewed at anyposition, thereby potentially improving a degree of image recognition.

Also, if a plurality of display modules is provided, images aredisplayed in a multi display performance mode, thereby potentiallyimproving beauty and effectively drawing customer attention.

Also, the brightness or transparency of a transparent display module isadjusted in response to determination as to whether a human body isdetected, thereby potentially reducing power consumption.

Also, a power supply unit to convert power is disposed in a frame,thereby potentially permitting the manufacturing of a display module ina slim structure and improving utilization thereof.

Although a few exemplary embodiments of the present invention have beenshown and described, it would be appreciated by those skilled in the artthat changes may be made in these exemplary embodiments withoutdeparting from the principles and spirit of the invention, the scope ofwhich is defined in the claims and their equivalents.

1. A display module comprising: a transparent display panel; and a framewhich fixes a side of the transparent display panel, wherein the framehas a communication unit operable to receive data, a controller operableto process the received data and to output a drive command based on theprocessed data and a display drive unit operable to drive thetransparent display panel in response to the drive command from thecontroller.
 2. The display module according to claim 1, wherein thetransparent display panel has a greater surface area than the frame anda smaller thickness than the frame.
 3. The display module according toclaim 1, wherein the communication unit is operable to perform wirelesscommunication and the controller is operable to process data receivedthrough the wireless communication.
 4. The display module according toclaim 1, wherein the frame has a hole and a power supply unit connectedto an external power source through the hole to receive power and toconvert the received power into drive power to drive the display module.5. The display module according to claim 1, further comprising ablocking member operable to block light, wherein the blocking member isprovided at an edge of the transparent display panel.
 6. The displaymodule according to claim 1, further comprising an anti-reflectivecoating film operable to prevent light from being reflected by thetransparent display panel, wherein the reflective coating film isprovided adjacent to the transparent display panel.
 7. The displaymodule according to claim 1, further comprising a heat insulation sheetoperable to block heat generated from transparent display panel frombeing discharged, wherein the heat insulation sheet is adjacent to thetransparent display panel.
 8. The display module according to claim 1,wherein the communication unit receives a broadcast signal.
 9. Thedisplay module according to claim 1, wherein the transparent displaypanel is operable to display images together with another transparentdisplay panel in a multi display performance mode in response to acommand from a server.
 10. The display module according to claim 1,wherein the frame has a recognition unit operable to recognize a tag andthe controller is further operable to read the recognized tag andcontrol an image corresponding to the read data to be displayed on thetransparent display panel.
 11. A display system comprising: a systembody having a first power supply unit; and a display module detachablymounted in the system body, wherein the display module comprises atransparent display panel, a frame which fixes the transparent displaypanel, and a drive module provided in the frame operable to convertpower from the first power supply unit into drive power and operable tocontrol driving of the transparent display panel.
 12. The display systemaccording to claim 11, further comprising a blocking member operable toblock light, wherein the blocking member is provided at the remainder ofthe transparent display panel wherein the blocking member is disposed atan edge of the transparent display panel.
 13. The display systemaccording to claim 11, wherein the system body comprises a showcasecomprising a main body, an opening at one side of the main body and astorage chamber in the main body, and wherein the display module ismounted in the opening of the showcase.
 14. The display system accordingto claim 13, further comprising an anti-reflective coating film operableto reduce external light reflected by the transparent display panel,wherein the anti-reflective coating film is adjacent to the transparentdisplay panel.
 15. The display system according to claim 13, furthercomprising a heat insulation sheet operable to reduce heat dischargedfrom transparent display panel to the storage chamber, wherein the heatinsulation sheet is at a side of the transparent display panel facingthe storage chamber.
 16. The display system according to claim 13,wherein the showcase further comprises a door mounted at the opening andthe display module is mounted at the door of the showcase.
 17. Thedisplay system according to claim 16, further comprising a detectionunit, which is provided in the frame and electrically connected to thecontroller, and which is operable to detect at least one of opening andclosing of the door of the showcase and to output a door signal, whereinthe controller is further operable to determine whether the door is openbased on a door signal and is operable to control an image displayed onthe transparent display panel to be reversed upon determining that thedoor is open.
 18. The display system according to claim 16, furthercomprising a detection unit, which is provided in the main body, andwhich is operable to detect a temperature of the storage chamber,wherein the controller is operable to determine whether the door is openbased on a change in the temperature of the storage chamber and isoperable to control an image displayed on the transparent display panelto be reversed upon determining that the door is open.
 19. The displaysystem according to claim 13, further comprising a detection unit, whichis provided in the frame and electrically connected to the controller,and which is operable to detect a human body and to output a human bodydetection signal, wherein the controller is further operable to adjust atransparency of the transparent display panel based upon the human bodydetection signal.
 20. A display system comprising: a system body havinga first power supply unit; and a plurality of display modules detachablymounted in the system body, wherein each of the display modulescomprises a transparent display panel, a frame which fixes thetransparent display panel and a drive module in the frame operable toconvert power from the first power supply unit into drive power andoperable to control driving of the transparent display panel.